Student Martin started working at Jim's Cafe in January 1985, where he worked alongside Gail, who was then married to Brian Tilsley. After Brian's death in 1989, Martin and Gail began a relationship despite a ten-year age difference (Martin being the younger of the two). When Gail fell pregnant, she decided to have an abortion, as she didn't want Martin to feel she was trapping him, but Martin stopped her and she gave birth to their son David in December 1990. Martin and Gail married in September the following year, and he adopted her older children Nicky and Sarah Louise the following month.
Martin and Gail had a happy marriage and the age difference wasn't often an issue. Martin spent four years at college studying nursing and it was there that he had a one-night stand with Cathy Power in 1994, but he and Gail got through this. In 2000, he had an affair with nurse Rebecca Hopkins and the heartbreak of Rebecca leaving him made Martin tell Gail the truth and divorce her. However, they remained good friends and Martin was still there for Gail and the children.
Martin later started a relationship with sixteen-year-old Katy Harris, much to the ire of her father Tommy who never accepted the relationship and kept trying to split them up. Tommy finally got his way when he got Katy to abort Martin's unborn baby, under the mistaken impression that Martin was having an affair. Martin split up with Katy and in the tragic circumstances which followed, Katy killed Tommy in a fit of rage and then took her own life.
Martin found greater happiness later in the year when he left Weatherfield for Liverpool with his new girlfriend Robyn and in 2006 Robyn gave birth to their daughter, Charlotte. Martin has not returned to Weatherfield since his departure but David occasionally visits him in Liverpool.
Martin Platt arrived as a school leaver who worked in Jim's Cafe. He had two GCEs and was studying at Salford Technical college. Jenny Bradley developed a crush on Martin and the two began hanging out, though Martin was more interested in friendship rather than romance. Just after Christmas 1986, Martin accompanied Jenny to a talent contest where she won first prize. As Martin was driving her home, Jenny persuaded Martin to let her have a go at driving the car. Unfortunately Jenny crashed the car and the accident left Martin unconscious in Weatherfield General. When Martin came to, Jenny asked him to take the blame for the crash and Martin agreed. However, when Jenny's father Alan Bradley confronted him about the accident Jenny broke down and told the truth. Jenny remained interested in Martin romantically for quite some time, although her crush finally ended when the two went grape-picking in France and Jenny fell in love with a Frenchman Patrice Podevin. However Martin and Jenny remained close friends. In 1988, Martin had a short-lived romance with Sally Webster's younger sister Gina Seddon. Soon afterwards, Martin became caught up in the drama between Alan and his partner Rita Fairclough when he began working for Alan and discovered that Alan was cheating on Rita. Martin covered for Alan but Jenny also suspected her father of having an affair and after talking to Martin she realised that her suspicions were true. The following year, Martin and Jenny interrupted Alan during his attempt to murder Rita and Martin chased after Alan as Alan escaped in his car.
1989-1999: Relationship with Gail Tilsley
Martin began comforting Gail after her husband Brian was stabbed in 1989. To everyone's surprise, they fell in love with each other. Gail fell pregnant and didn't think it was fair for someone young like Martin to become a dad, so planned to have the baby aborted. However, Martin found out and managed to stop her. On Christmas Day 1990, they had a baby boy and named him David. They got married in 1991 and Martin adopted Gail's two children Nick and Sarah, from her previous marriage to Brian.
1999-2002: Affair and marriage breakdown
In 1999, Martin had an affair with nurse Rebecca Hopkins. Martin was all set to leave Gail for Rebecca but his plans changed when it was discovered that Sarah was pregnant at the age of just thirteen. Rebecca eventually left Weatherfield and Martin and Gail couldn't patch up their relationship, so later divorced. Gail went on to marry Richard Hillman, who turned out to be a serial killer who murdered Maxine Peacock, his ex-wife Patricia and then attempted to kill Gail and the children. However Martin saved them along with Kevin Webster and Tommy Harris.
Even though they were divorced, Gail and Martin still remained good friends afterwards and Martin would normally come round for tea with Gail and the children and Sarah's daughter Bethany.
2002-2005: Relationship with Katy Harris
In 2003, Martin fell in love with sixteen-year-old Katy Harris. Katy's father, Tommy, who had previously been Martin's friend, disapproved, and attacked Martin physically, whilst Katy's brother, Craig, attempted to kill Martin by interfering with the brakes on his car. Katy's parents were even more unhappy when she left school and got pregnant. Sally Webster (one of Martin's ex-girlfriends) was having an affair with work colleague Ian Davenport, and her friendship with Martin, who was working particularly late hours, made Tommy and Angela Harris believe they were having an affair. They told Katy, who moved out of Martin's flat and had an abortion. When Gail told them the truth, Katy was devastated. She confronted Tommy in a rage, and attacked him with a wrench, killing him. Because of the bad blood between Martin and Tommy, Martin was at first arrested for the murder. Even though Angela only witnessed the murder of Tommy, she confessed to doing it. Martin was released, and Angela arrested. Katy was hysterical, and as a diabetic, decided to commit suicide by forgoing her insulin injections and eating sugar. Martin, Sarah and Sarah's then boyfriend Scooter Makuna managed to get Katy to hospital, but she later died.
2005-2018: Life away from Weatherfield
Martin left Coronation Street with new girlfriend Robyn in November 2005. David was devastated by this and didn't talk to Martin for some time, but they reconciled before he left. In January 2006, David returned after visiting Martin and revealed that Martin and his girlfriend were expecting a baby. Later that year, Robyn gave birth to their daughter, who they named Charlotte.
Martin was supposed to return for Sarah's wedding to Jason Grimshaw in 2007 to give her away, however couldn't make it as his daughter was ill. David went to visit Martin in 2009 as he had enough of his mother Gail and her boyfriend Joe McIntyre and returned a couple of weeks later.
In July 2015, David went to stay with Martin in order to take a break from problems at home, involving stepson Max's behavioural problems and also conflicts with Max's father Callum Logan. When he returned, he told Gail that Martin had bought a new house with a big garden and a posh kitchen and had received a promotion at work. Although Martin sent his love on to Gail, David pointedly told her that his dad had done really well in life since he had split from her.
In March 2018, Martin and Robyn were expecting their second child and planning to emigrate to New Zealand. Later in the month, David suddenly turned up on Martin's doorstep with the kids in tow in order to stay with him for a couple of days. Martin could see that there was something troubling David, and urged him to open up to him. Martin came to the conclusion that David was upset because of him emigrating to New Zealand, although in reality it was because David was harbouring a secret involving him being raped by his friend Josh Tucker a few days prior. Martin told David that he could always visit New Zealand as it was a wonderful place to be, which gave David an idea to instead emigrate with his dad and start a new life there. When David returned home, he told his family that he was planning to move away with the kids to New Zealand and start afresh, much to their shock at the sudden development.
Martin turned up on Coronation Street for the first time in over twelve years, and he met David's girlfriend Shona Ramsey. When Josh overheard Martin discussing David's plans to emigrate, he expressed his "concern" for David's welfare. When David found out, he told Martin that Josh was no friend of his and dismissed his concern. David is adamant that he wants to emigrate, regardless of the fact Max and Lily want to remain in Weatherfield. Martin tells him that he could always visit any time, but David makes out that he is unable to live in the same street where Kylie was murdered, and refuses to see goodbye to his dad. However when Martin is about to leave, David arrives to see his dad off, and informs a delighted Martin that he has decided to remain in Weatherfield and not make the hasty decision to emigrate after all.
Martin's 2005 departure came due Sean Wilson being axed when he refused to take part in a storyline involving Martin having a relationship with an underage girl. Sean opposed due to having a family of his own. He gave up acting and started a career in cheese making, although he has stated he may like to return to Coronation Street. But in 2013, Sean Wilson vowed not to return to the street, as mentioned in his book The Great Northern Cook book. He is quoted "By 2005 I knew my tenure on the Street had to end. An editorial decision was made that Martin should embark on an underage relationship, something that made me uncomfortable. I picked up my coat and left in September in that year ending 21 years of massive fun with a fabulous on-set family." He then goes onto saying “I will act again, but never with "Coronation Street". They were very rude to me when I left, I would rather walk down any other street even if I had a nail in my shoe.”
Despite prior claims that he wouldn't return, in January 2018 it was reported that Wilson would be returning to the role of Martin after an absence of just over twelve years, which would tie into a storyline involving David Platt being raped by Josh Tucker. In an interview with Digital Spy in March 2018 - a week prior to Martin's return scenes airing, Wilson stated that it was the first time he was offered a chance to return to the show, and when asked about what changed his mind in the years following his exit and firmness not to return, he stated: "Lots of things have changed. There was a juxtapose of editorial thoughts at the time, and I morally felt that I had to stand very, very firm on the decision that I made, so there came a parting of ways. But things move on, especially in showbusiness and maybe the people that were in charge have moved on. They've all split and gone elsewhere in showbusiness. When this came around, I thought the scripts were ace, which I was pleasantly surprised with because Martin's not been there for 12 years. I thought it might just take the writers a while to get to know the character again, but clearly not. There's a real positiveness about the place and there's been a real warmth from me. I couldn't have asked for a better way to come back, so I'm really pleased. I questioned myself before I walked into the building, but I've been really pleased with the way it's all turned around."
First and last lines
"Uh, yeah." (First line)
"I'll call you when I get there, see you." (Final line, to son David)