The Martin family is one of the founding families of Pine Valley. Joe was a widower in January 1970 trying to raise his children, Jeff and Tara, in the Martin family home with the help of his wonderful mother, Kate. Joe fell in love with Ruth Brent, a nurse at Pine Valley Hospital, who was married to an abusive man, Ted Brent. After Ted's death in an automobile accident, Joe and Ruth were married. Together they adopted son, Tad and had a change-of-life baby, Joey. (There was also a son Bobby, who went to the attic in search of his skis and has never been seen or missed since). Joe had a brief attraction to Leora Sanders, a patient of his, who was being abused by her husband, Kirk. Joe and Ruth separated briefly over his feelings for Leora. After the death of his very good friend and co-worker, Dr. Charles Tyler, Joe inherited the position of Chief of Staff at Pine Valley Hospital. Over the years, Joe has helped to build and keep his nuclear family together and more recently has rebuilt the Martin family home which was destroyed during the tornado that almost took Tad's life. Joe has been the solid rock upon which everyone in Pine Valley has turned to at one time or another for sound advice and fatherly love.
Joe's life nearly came to a premature end in July 1997 when, after a heated confrontation with Dimitri, Joe suffered a massive heart attack. Joe was unconscious for a long time and there was fear that he would suffer brain damage from lack of oxygen. Fortunately, there was no brain damage. There was, however, irreparable damage to his heart.
In March 2002, Joe was forced into stepping down as Chief of Staff of Pine Valley Hospital when David threatened to expose some medical mistakes Joe had made. The mistakes were attributed to Joe's age as well as the fact that he was not as up-to-date on the latest medical breakthroughs as his counterparts. As Joe stepped aside, his son, Jake, was named to his former post.
Joe was thrilled to learn the truth from Tad about Josh being Jeff and Erica's son, but reluctantly agreed with Erica that telling Josh might not be the smartest thing. He was even happier when his son, Jeff, came home after a long absence.
Joe realized that Greenlee got an infection after she was rescued from the bomb shelter. A nurse at the hospital alerted Joe that a person that had the same symptoms as Greenlee came to the hospital for treatment. Joe saw that the other person was Frankie Hubbard. Joe called in Dr. Angela Hubbard to come treat both Greenlee and Frankie since she was an infectious disease specialist. Joe was relieved when Angie saved both Greenlee and Frankie's lives.
Joe and Ruth were thrilled when Aidan Devane rescued their son, Jake Martin, in Darfur but Jake wanted to go back to Darfur to help the people there. Joe and Ruth persuaded him to not go back and stick around in Pine Valley. Jake decided to stay home.
While Joe visited his daughter, Tara Jefferson, during the holiday season of 2008, David Hayward called him up and blackmailed him into stepping down as Chief of Staff. Joe stepped down and David Hayward became the new Chief of Staff at Pine Valley Hospital.
As the new year of 2010 rolled in, Joe and Ruth decided they were ready to make a change and they moved from Pine Valley to Florida. They wanted to enjoy the warmer weather and spend time with Tara and her family. They returned to Pine Valley briefly to attend Tad's wedding to Cara Castillo, although Joe was not convinced the marriage was in the best interest of the family. Cara and Jake were previously married and although Tad was marrying Cara to secure her legal status in the country, Joe worried about the effects Cara's continued presence would have on Jake and his marriage to Amanda. Joe set aside his misgivings regarding Cara when she was in trouble with the hospital board. He spoke to the board on her behalf.
In September of 2011, Joe took a position as a consultant at Pine Valley Hospital and he and Ruth moved back. They were reunited with family and friends and celebrated the news of Tad's recent engagement to Dixie. They also joined many other Pine Valley residents at a party hosted by Adam Chandler at his mansion. During the party, they toasted the love of family, friends, and neighbors as a shot rang out.
Time advanced five years between the final episode on ABC and the first episode of Prospect Park's online version.
Five years later, Joe remained in Pine Valley and continued his work at the hospital. In Tad's absence, he supported Dixie while J.R. emerged from the coma that he had been in for the past five years which had been the result of being shot by David Hayward. Dixie and Joe were both surprised when David was unexpectedly released from prison and they feared that he would seek retaliation against J.R. once again since J.R. had killed David's daughter Marissa. Instead, David approached Joe and asked him to garner the hospital's support for the diagnostic biosensors he had created. Joe turned him away and ordered him to stay out of the hospital.
Both Dixie and Joe were caught off-guard again when Billy Clyde Tuggle was revealed to be alive and back in Pine Valley. Billy Clyde insisted that he had changed and Joe was surprised to learn that he had moved into Palmer Cortlandt's former home. While Joe kept an eye out for Billy Clyde, he helped Angie and Jesse deal with the kidnapping of their daughter Cassandra by Russian sex traffickers. As Jesse and Angie separately struggled to help Cassandra, Joe offered words of advice and encouragement to them both.