Former Doctor at the Llanview Hospital clinic
Carol MacIver (sister)
Colin MacIver (brother; twin; deceased)
Held Matthew Rappaport hostage in an attempt to escape from jail
Held Lindsay Rappaport, and Jessica and Natalie Buchanan hostage
Tried to force Nora Buchanan into a suicide pact
Switched Lindsay Rappaport's medication to make her appear delusional
Escaped from Statesville Prison and kidnapped Nora at gunpoint [Jan 2012]
Attempted to inject Nora with memory erasing drug [Jan 2012]
Shot Bo Buchanan during a scuffle [Jan 2012]
Knocked out by Sam Rappaport and nearly suffocated by Lindsay Rappaport, who mistook him for his dead brother Colin 
Pushed out of window by Sam Rappaport
Knocked out by Lindsay and tied to large wheel
Shot by Bo Buchanan during scuffle [Jan 2012]
Troy was the identical twin brother of the evil doctor Colin MacIver. Troy appeared in Llanview at the reading of Colin's will. He did not get a warm reception; Sam Rappaport knocked him out and Lindsay tried suffocating him with pillows while he was unconscious. Because of his uncanny resemblance to Colin, the citizens of Llanview distrusted him.
Troy moved into an apartment above Break Bar, where he and Sam got into another fight and Sam shoved him out the window. The two men disliked each other from that point forward. Troy began to have feelings for Nora Buchanan, whom Colin had kidnapped and held hostage for five months. Nora had been injected with a memory-erasing drug during that time, so she had lost three years of her memory, but she firmly believed Lindsay was the one who had done it to her.
Troy wanted to earn Nora's trust, and his chance came when Nora's son Matthew was diagnosed with a rare muscle disease. Troy tried a new treatment on it and cured him. Nora was thrilled, and a fragile truce was established between Troy and Sam.
Colin was publicly blamed for Nora's memory loss, and Troy became determined to clear Colin's name and prove once and for all that Lindsay had given Nora the dose. He gave Nora pills to restore her memory, but she was able to remember everything but the crucial moment when Lindsay pricked her with the needle. Troy hatched a plan to pretend to "fall in love" with Lindsay, and get her to trust him so she would confess. He tried many tactics, from trying to pry it out of her to giving her a truth-inducing serum. Nothing worked.
Finally, Troy proposed to Lindsay and the two were scheduled to fly off to Paris for their wedding. Troy purchased an old funhouse outside of town, with fake panels and mazes. Pretending to be Colin, he forced Lindsay to come to the funhouse and "rescue Troy." Lindsay did not know of the false panels, so Troy was able to go from room to room while it took Lindsay a long time, thus pretending to be Colin, then Troy again.
Lindsay confessed, and the confession was taped. Lindsay found out it was a trap and hit Troy over the head with a crowbar, then chained him to a huge wheel. Days passed, and Troy still refused to tell her where the tape of her confession was. He was bitten by a Black Widow spider, but was able to recover.
Starr Manning wandered into the funhouse, and tried telling people Troy was in there, but because of her record for lying, no one believed her. She brought Troy food and eventually told Sam where Troy was. An electrical fire had started in the funhouse, and Sam arrived just in time to save Troy. The two men narrowly escaped.
Lindsay and Nora found the tape of Lindsay's confession at the same time and fought it out, but Nora got it in the end. Lindsay was arrested and sent to prison, but eventually was pardoned after saving the life of the governor's granddaughter. Later, a desperate Lindsay tried to murder Troy but ended up killing Sam instead. Wanting to destroy Lindsay and keep her locked up, Troy switched her medication to make her appear delusional. Meanwhile, he became obsessed with Nora and finally attempted to force her into a suicide pact, so they'd die together, by drinking poisoned wine. Luckily for Nora, she got away and Troy was arrested. Although he tried escaping from prison, on both occasions he was apprehended and sent back to prison.
On New Year's Eve, hundreds of inmates escaped Statesville Prison during a major blackout and an armed Troy MacIver stunned Nora by showing up at her home. Troy was still in love with Nora and wanted to start a new life with her. Nora tried to protest, explaining that she was married to Bo, but eventually decided to go along with Troy until Bo could arrive. When Troy realized that Bo was on his way, he bound and gagged Nora and drove to a secluded mountain cabin where he planned to inject her with the same memory erasing drug that Lindsay had given Nora years earlier. Just before he could administer the injection, Lindsay burst into the room and claimed to have just killed Bo. Nora was devastated but then stunned when Bo appeared and tried to get the jump on Troy.
The two men fired shots and Troy fell to the ground, wounded. Bo explained that Lindsay had realized what Troy was up to and had warned Bo, and together they rescued Nora. Bo gave Lindsay the keys to his vehicle and told her to send an ambulance for Troy. As soon as she left, Bo collapsed and Nora realized that he had been shot as well. Nora pleaded with Troy to save Bo's life, and he reluctantly agreed. Troy tried to revive Bo but when he couldn't get a pulse, he told Nora that Bo was dead and fled the cabin. Bo eventually was revived. Later, he learned that all of the inmates who had escaped from jail had been recaptured, except for Allison Perkins.