Zach Slater was born Alexander Cambias, Jr. Growing up, Zach felt the tyrannical rule of his father, Alexander, Sr. Alexander expected his eldest son to run the family empire as Alexander saw fit, a life Zach did not want to lead. With the help of his younger brother, Michael, Zach faked his death and adopted the new identity of Zach Slater, the name of a boarding school friend.
Zach worked odd jobs and eventually built his own empire of casinos. Zach met Maria Santos Grey, and the two fell in love. Maria was suffering from amnesia, and going by the name Maureen Gorman. Maureen couldn't remember her past, and Zach wanted to forget his. Their desire to live for the moment drew the two together and fed their love. Their affair was cut short when David Hayward, who was trying to hide Maria from being discovered by her family, lied and told her the police were closing in on her because of an imagined murder David told Maria she had committed, as a way to keep her on the run. Maria was forced to leave Zach. Zach assumed he would never see her again.
Years later, Zach learned that Michael had been murdered following an extended stay in Pine Valley. Soon Erica Kane, one of Michael's many enemies and a suspect in his murder, arrived at Zach's casino for an extended stay. Zach kept close tabs on Erica as he researched her family and all those in Pine Valley that had reason to hate Michael. During the course of his research, he found that his beloved Maureen was living in Pine Valley, after having regained her memory. Zach traveled east to Pine Valley, where he made plans to open a casino outside of town.
Zach made his presence known to Maria, who was affected at the sight of him. The feelings between the two were strong, and Zach wanted to resume their relationship, but Maria explained that she was married. She did not tell her husband, Edmund, who was paralyzed in a wheelchair, that she'd had a relationship with Zach during the time she was away from Pine Valley. Edmund eventually discovered Maria and Zach's past, which built enmity between Zach and Edmund.
Zach met Bianca Montgomery and grew to like and respect her. Bianca had killed Michael, which Zach had trouble comprehending, given her kind and compassionate nature. Zach was unable to accept that Michael had become a monster, assaulting women and ruining lives. The Michael that Zach remembered was a sweet, trustworthy young man. Zach was convinced that someone close to Bianca---Erica, or Bianca's sister Kendall Hart---had killed Michael. Michael had had lots of enemies in the town, and Zach was not impressed by the moral composition of the residents.
At the grand opening of his casino, Zach designed a murder mystery game whose elements were similar to the Michael Cambias murder case. Watching via security cameras, Zach hoped to weed out the real killer by observing them play a game similar in design to Michael's real death. Maria discovered him and confronted him on his action, and Zach revealed to her that he was Michael's brother. During the course of the murder mystery game, an unknown assailant shot Ryan Lavery.
Maria tried to convince Zach that Bianca had killed Michael, and that Michael was a horrible man. Maria promised Zach that she would help him accept the truth about Michael and come to terms with it. Edmund did not want Maria around Zach, so Maria had to keep her meetings with Zach a secret. Finally Zach was able to accept the monster Michael had become, and broke down in Maria's arms. Erica saw the two together and reported everything to Edmund. Furious that his wife continued to see Zach when she had promised she wouldn't, Edmund initiated divorce proceedings. Despite his strong feelings towards her, Zach respected Maria's determination to make her marriage work.
Zach was shocked when Ethan Ramsey arrived in town and claimed to be Alexander Cambias Jr.'s son. Ethan's story, of Alexander Jr. impregnating maid Hannah Nichols, only to die soon after, rang true with Zach. He remembered sleeping with Hannah before faking his death. Zach had Ethan's DNA tested in secret and learned that they were father and son. Shortly after, Zach announced to the whole town that he was really Alexander Cambias, Jr., and apologized to Bianca for Michael's actions. Zach told Ethan that they were not father and son. Zach later confessed to Maria that Ethan was his son, but he would deny Ethan the Cambias name at all costs, because he did not want the Cambias money to corrupt Ethan as it had Michael and their father.
Ethan was arrested for shooting Ryan Lavery, and Zach worked behind the scenes to clear him. While Ethan was incarcerated, Zach took shots at Ryan and Ryan's wife, Greenlee. Zach was confident that doing so while Ethan was still in prison would weaken the case against Ethan. Ethan was granted bail. Ryan accused Zach of taking the shots at him, and wondered if Zach was responsible for both shootings.
Zach remained determined to keep Ethan from obtaining the Cambias name, and wanted him to leave town as soon as he was cleared of the charges against him. To that effect, Zach tried to convince Kendall, who was dating Ethan, to break up with him, so Ethan would leave town once the trial was over. Kendall refused, and the ordeal only drew Ethan and Kendall closer, while building the animosity between Ethan and Zach.
Determined to get Kendall out of Ethan's life, and in doing so, get Ethan out of town, Zach presented compelling evidence to Ryan that would suggest that Kendall was responsible for poisoning Greenlee. Zach was also elated when Miranda, Bianca and Michael's presumed dead daughter, was revealed to be alive. Ethan had his DNA tested against Miranda and learned he was Zach's son. Ethan confronted Zach over denying him and declared war.
Maria resisted her feelings for Zach and told him that she was reconciling with Edmund. Zach respected her wish, but soon discovered security footage that showed the wheelchair-bound Edmund could walk, and had been lying to Maria about his paralysis. Zach prepared to tell Maria, but Ethan waylaid him in the Wildwind barn. The two fought, and Ethan knocked Zach out. When Zach awoke, the barn was on fire, and Edmund was unconscious on the ground. Zach nearly died in the fire, but Ethan saved him. Edmund died from his injuries, and Ethan lied and told the police he had witnessed Zach kill Edmund.
Zach told Maria that Edmund had been lying to her and had been able to walk, but she refused to believe Zach and accused him of murdering Edmund out of jealousy. Zach was arrested. Zach, feeling betrayed by his son and the woman he loved, confessed to the murder as a way to hurt them. Lily Montgomery, who had actually witnessed the crime, stepped forward and declared that Zach was innocent. Zach was cleared of the crime. Maria apologized to Zach for not believing him, but he was hurt by her lack of faith in his innocence. Slowly, the tension between them melted, as Maria admitted to Zach that she had never stopped loving him, but that her focus had to be on repairing her damaged relationship with her children. The two former lovers parted with a final kiss goodbye.
Zach sued Ethan for control of Cambias Industries, which Ethan had taken over. As revenge, Ethan had Zach's casino shut down. Kendall had broken up with Ethan, disgusted over his lies about Zach's guilt. Zach proposed to Kendall that they marry as the ultimate form of payback to Ethan. Additionally, Kendall would regain Zach's gaming licenses for him and help him run the casino, and would keep Bianca and Miranda's interest in Cambias Industries after Zach had regained control. Kendall agreed, and the two were married in secret. Shortly after, Ethan made a loving plea to Kendall to reunite, but Zach dropped the bombshell that he had married Kendall. A furious Ethan fought Zach, and declared his father dead to him.
Shocked by the depth of his son's pain, Zach called off his lawsuit to regain Cambias. He offered to let Kendall out of their marriage, but Kendall chose to remain married to Zach, desperate for a loveless marriage as a means to keep her away from the inevitable pain that love brought. Zach and Kendall began to develop genuine feelings for each other, but neither one wanted to admit it. Kendall turned on Zach after learning that he was responsible for the blackout that had resulted in Kendall having herself implanted with Ryan's sperm so that she could give Ryan and Greenlee a baby, and the two divorced. Zach was also devastated to lose his son, Ethan, in the Mardi Gras ball explosion. He encountered Dixie Cooney at the cemetery, and soon became enmeshed in her quest to get certain information from Greg Madden. Zach had a motive of his own -- he wanted to make sure that Greg could never hurt Kendall.
Zach "kidnapped" Kendall from Madden's island of pregnant surrogates and took her on a boat ride, where the two of them remarried. Once they returned to Pine Valley, Kendall was seriously injured in an accident at Fusion. Determined to do what he could to make sure that Kendall's son, nicknamed Spike, survived, Zach barricaded himself in her hospital room to give Spike enough time to be healthy. Luckily, Spike managed to make it safely through childbirth, even though he was very weak, but Zach faced criminal charges for what he had done. A contribution to the judge's campaign saved Zach from jail time, but he faced Kendall's ire over his refusal to seek vengeance against J.R. because of a promise he had made to Dixie. Kendall was finally able to understand Zach's vow to Dixie and offered to assist Dixie, who was trying to find her daughter, as thanks for Dixie giving Zach the information he had needed to save her from Madden.
Zach and Dixie were charged with the murder of Greg Madden. During the trial, Tad gave testimony that would put doubt into the jury's mind that Zach and Dixie had killed Greg. Tad confessed to burying Greg Madden alive and said that had caused his death. Zach and Dixie were acquitted, and Tad was not charged due to the double jeopardy clause in the Constitution.
A killer known as the Satin Slayer appeared in town, and began picking off several women and injuring others. The killer was revealed to be Zach's father, Alexander Cambias Sr. Zach's father killed and injured people close to Zach as punishment for Zach not being a good child. Alex Sr. kidnapped Kendall, and Zach tracked them both to Las Vegas. Zach rescued Kendall, and his father was arrested. The judge deemed Alexander Cambias Sr. to be insane and had him transferred to Oak Haven.
On the day of the transfer, someone shot Zach's father, but he survived. The shooter was revealed to be Hannah Nichols, Zach's ex and mother to Zach's son, Ethan Ramsey. Hannah had just returned to town in hopes of having Zach all to herself again. When Hannah begged Zach to impregnate her one night, Zach refused and told her he was devoted to being with Kendall. Hannah left town, and Zach stayed with Kendall.
When Greenlee got into a car accident with Spike, Zach and Kendall faced tough times, since Kendall had gone into early labor with their child. Despite a tough delivery, Kendall gave birth to Ian, her son with Zach.
Zach and Adam met one day, and Adam said that J.R. had been kidnapped. J.R. would be released if Adam came up with a large sum of money that he did not have. Zach said he would loan Adam the money on one condition: Zach would get Chandler Enterprises and Chandler Mansion. Adam agreed. Eventually, Adam got enough money to get back his company and his house. Zach said it did not mean much to him anymore.
Zach was destined to make Greenlee pay for nearly killing Spike. He and J.R. teamed up to try to convince Greenlee that there were still some embryos of hers that were viable and that had not been defrosted the night of the power outage in 2005. There was a catch: Greenlee would have to sell her shares of Fusion in order to find out the location. In reality, there were no embryos out there, and Greenlee found out, so she refused to do business with Zach.
Hannah once more returned to town, and Zach hired her at Cambias Industries. Again, Hannah attempted to strike up a relationship with Zach, but he refused.
One night, Richie Novak stole J.R. Chandler's car and ran Zach Slater down. He left Zach for dead in the woods, but Greenlee found Zach and helped him. Unfortunately, they both got trapped in a bomb shelter. Their loved ones, Kendall and Aidan, thought they were dead, so Kendall and Aidan had a one-night stand. Eventually, Kendall found plans to the bomb shelter, and she and Aidan went there. They rescued Zach and Greenlee. Zach and Greenlee became friends after that and buried the hatchet over what Greenlee had done to Spike.
Zach, Kendall, Aidan, Greenlee, Ryan, and Annie found out that Hannah had shot Ryan when she aimed at Kendall. Zach chased her to Miller's Falls, where Hannah slipped over a ledge. Zach caught her, but Hannah let go.
Zach found out that Kendall had cheated on him with Aidan while he had been in the bomb shelter. He and Kendall did not split up, since he was most upset that she could not trust him to tell him the news. When Greenlee found out about Kendall and Aidan's one-night stand, she blasted Zach for not telling her. However, she and Zach still remained friends.
Zach started to notice that Annie Lavery was becoming unbalanced. He convinced her to get help with a psychiatrist and recommended she see one that he knew. At Annie's meeting with the doctor, she confessed to killing her brother, Richie. What Annie did not know was that Zach was in the other room and recorded her confession. Annie broke a window after she heard a sound and saw that Zach had set her up.
Ryan sued Annie for custody of Emma. Zach told Annie at the hearing that, if she did not give up custody of Emma, he would play her recorded confession to the police and have her arrested for Richie's murder. Annie agreed to let Ryan have custody.
Zach's employee, Josh Madden, embezzled from Cambias Industries, and Zach wanted revenge on him. Zach was even more upset when Kendall helped Josh escape town. It put a strain in Zach and Kendall's marriage.
During tornadoes that struck Pine Valley, Zach went out driving to the store, but a tornado caught up to his car, and he crashed into a tree. He made it home and saw an unconscious Kendall. He went looking for Spike and Ian in the rubble and found an unconscious Bianca. Bianca pulled through and had a reunion with Zach. Viewers learned that, months earlier, Zach had gone to visit Bianca in Paris and had met her girlfriend, Reese Williams. Bianca had asked Zach if he would donate his sperm so that she could get pregnant and raise a baby with Reese. Zach had agreed and become a donor, but neither he nor Bianca had asked Kendall beforehand if it was okay.
Zach became frantic to help Kendall, but David told him that there was little hope and she was dying. The only thing that would save Kendall would be a heart transplant. Zach said he would find a heart, even if he had to kill someone to get it.
Josh Madden returned to town and tried to rob Zach's casino. Josh took Reese hostage, but Reese got away and there was a shootout between Josh and Zach. Zach shot Josh dead and then demanded they keep him alive, since they needed his heart for Kendall. Josh's heart was a match for Kendall, and David transplanted it into her. Kendall woke up, and Zach broke the news to her that he had fathered a baby with Bianca without telling her.
When Kendall left Bianca and Reese's wedding in her car after hearing Bianca would not leave town with Reese and Gabrielle, Zach got into the car. Kendall drove erratically and almost hit Greenlee, who was on her motorcycle. Greenlee went over a cliff and was presumed dead. Zach told Kendall he would say he was driving the car.
Although Greenlee's death was ruled an accident, Ryan sought revenge against Zach. He went after Zach's company, Cambias Industries, and Zach's wife. Zach left Kendall at Greenlee's memorial to be with Reese at the hospital. Reese was temporarily blinded when she tumbled down a flight of stairs and crashed into a tray of glassware. Shards of glass had flown into Reese's eyes.
Zach remained friends with Reese and was there for her during her recovery. This pushed Kendall and Zach farther apart. Ryan and Kendall grieved Greenlee's death, and they slept together. Zach and Kendall divorced, and Kendall continued her affair with Ryan, while Zach slept with a woman he met at the casino, Liza Colby. Zach made sure Kendall learned of his one-night stand.
The feelings between Zach and Kendall were pushed aside when Ian needed heart surgery. The Chandlers provided a heart valve prototype, which David Hayward used. When Ian's heart valve replacement failed, Kendall and Zach witnessed Ian flatline, and they blamed Adam for their son's death. The heart valve was defective. Zach and Kendall separately went to the Chandler mansion to kill Adam Chandler. Someone had murdered Adam's brother, Stuart, the same evening. Ian recovered, but both Zach and Kendall were suspects in Stuart's murder. Zach remarried Kendall so they could not be forced to testify against each other.
Kendall was charged for the murder of Stuart Chandler, but she swore she had not pulled the trigger. Zach blackmailed Liza into representing Kendall. During Zach's one-night stand with Liza, he had learned her she had faked her pregnancy. Liza planned to adopt a baby, but pretend it was biologically hers. Liza had romantic interests in Zach, and she used the time working on Kendall's case to get closer to Zach. His marriage to Kendall was in name only, but he did not respond to Liza's advances.
After months of accusations of murder, Kendall believed she had killed Stuart. Zach remained confident she was innocent. When Kendall was sentenced, Zach hired a look-alike to take Kendall's place in prison. The real Kendall was hidden upstairs in her home where she could still care for her children. Zach believed Ryan's daughter, Emma, knew more about the murder than what she had claimed. Emma stated she had seen Kendall shoot Stuart. Without Ryan's consent, Zach pressured Emma to remember what she had really seen. However, Ryan stopped Zach before Emma could speak.
From her hideout at home, Kendall secretly watched Liza continue to make moves on Zach, and Kendall did not like it. Kendall tried to make her marriage to Zach physical, but he refused. He was still hurt by her affair with Ryan. Despite Kendall's protests, Zach continued to work with Liza to investigate other suspects. As part of the investigation, Liza and Zach were dance partners at the charity dance marathon, which was televised. Zach and Liza danced closely and shared a kiss for the benefit of the cameras. Kendall was enraged and showed her jealousy when she risked her freedom and showed up at the dance marathon. Aidan Devane found her.
The look-alike that Zach had hired refused to return to prison after she was stabbed, so Kendall took off with Aidan. Through a poetry website, Kendall and Zach sent messages to one another. They were unaware of Aidan's obsession with Kendall. Aidan intercepted messages and changed them so Kendall believed Zach had fallen for Liza. When Zach showed up to see Kendall, he saw Kendall and Aidan in a compromising position. Aiden was actually with Kendall's look-alike.
After Kendall was cleared of Stuart's murder, she did not return home immediately. Aidan threatened to harm everyone Kendall loved if she left him. A friend of Aidan's told Zach the truth, and Kendall returned home. The Slaters left Pine Valley to reconnect as a family.
Kendall returned to Pine Valley when Ryan suffered an aneurysm, and Zach followed shortly after. They learned Greenlee was alive, but married to David Hayward. Kendall wanted to help Ryan and Greenlee reunite, so Kendall and Zach moved back permanently. Zach left Pine Valley soon after to tend to casino business. He wanted to sell the casino, but his business partners were not happy with that decision, When Zach returned from his trip, he helped Greenlee and Ryan on Kendall's behalf. Greenlee stood accused of David's murder. Zach helped Ryan and Greenlee find proof of her innocence. While Zach was helping Ryan and Greenlee, his plane crashed. He was presumed dead, although his body was not found.
In August of 2011, David led Greenlee to believe her former husband Leo could still be alive and she allowed David to take her to one of his secret medical compounds. David drugged Greenlee and when she awoke, she was in a room with a patient that was hooked up to medical equipment. Greenlee expected to see Leo but instead saw Zach. He was one of David's patients and had undergone David's experimental Project Orpheus treatments. Zach was in need of medical attention and suffered seizures in Greenlee's presence and he mistook her for Kendall. He was taken to the hospital for treatment and was reunited with Kendall and his sons.
One of Zach's doctors was Griffin Castillo and Zach quickly realized there was something going on between Griffin and Kendall. Greenlee explained to Zach that after his presumed death, Kendall required heart surgery and Griffin was her doctor. Griffin also helped to protect Kendall from the man that had been behind Zach's plane crash. Zach was grateful that Griffin had been there for Kendall in his absence but he made it clear to Griffin that he was back and could now look after his own wife.
Kendall and Zach tried to reclaim the life they shared before Zach's plane crash and Kendall agreed to stand by her husband when he publically offered his support to David Hayward. Many Pine Valley residents, including Griffin and Ryan, believed David's experimental Project Orpheus needed to be shut down. Zach credited David with saving his life and agreed to partner with David in Project Orpheus.
Project Orpheus was in danger of being stopped with Griffin threatened to inform the FDA of the experimental procedures David had conducted. Shortly after, Griffin disappeared and during a meeting with David, Zach admitted he had killed Griffin to prevent him from destroying Project Orpheus. Ryan and Greenlee interrupted the meeting and Zach shot Ryan and left him to bleed without receiving medical attention from David or an ambulance. David was shocked by Zach's actions and confessed he should have let Zach's murder happen the way the casino partners had planned.
David admitted he had known about the plans for Zach's plane to crash and the police received David's confession. Ryan and Griffin emerged alive and injury-free and revealed that they had all worked together with Zach to bring David to justice. David was taken into police custody.
After Zach's fake partnership with David was over, he and Kendall focused on their relationship and they hosted a family barbeque. Ryan and Zach announced their decision to partner together in a charity foundation named after Myrtle Fargate and Bianca and her girlfriend Marissa presented Zach and Kendall with tickets for a romantic getaway in New York.
The celebratory mood continued when Stuart Chandler was also revealed to be alive as part of Project Orpheus. Adam Chandler hosted a party to welcome his brother home and Kendall and Zach attended. They joined many other Pine Valley residents in celebrating life in their town as a shot rang out.