Martin Andrew Downes (né Lynch) was Bet Lynch's son whom she gave up for adoption when she was sixteen.
Bet got pregnant with Martin when she slept with a man called Joe Mason. Unable to take care of him, she left him with the Downes family of Eccles. Many years later, Bet cried as she told Irma Barlow about the day that she watched from behind the bedroom curtains as the corporation van drove off with the baby.
Martin was always curious about his birth parents. When he was sixteen, he went to London to begin tracing his mother and by 1974 he knew that she was called Elizabeth Lynch at the time of his birth in 1956 and that she was working as a barmaid in Weatherfield. By that time, Martin was serving with the Royal Transport Corps.
On his next leave, he and his Army colleague Steve Baker stopped by Weatherfield to search the local pubs for an Elizabeth of the right age. They struck lucky at the Rovers Return, which had two barmaids by that name. The first - Betty Turpin - was ruled out when Steve learned that her maiden name was Preston, but when he heard Annie Walker refer to "Miss Lynch", Martin realised that he's found his mother. Bet then arrived and promptly changed into a revealing dress she'd bought for Maggie Clegg and Ron Cooke's wedding and lapped up the attention which came her way from the male bar patrons. Repulsed by her overt sexual nature, Martin left the pub without informing her of his identity.
While stationed in Northern Ireland, Martin was out drinking with some lads and died when their car hit a tree. As Martin had been adopted as a baby, Bet wasn't notified of his death and so Steve went to the Rovers on his next bout of leave to break the news to her. Although she never knew him, Bet felt that she'd accomplished something through him and took his death hard; she considered taking her own life with a load of aspirins until Eddie Yeats stopped her and made her tell him about Martin.
When Bet was burgled in 1980, her only photograph of Martin was stolen. Bet was devastated as she knew it was the frame the thief was after and the picture would just be discarded. Ten years later, Bet had another uncomfortable reminder of what she'd lost when Ivy Brennan, using a medium, was given a message from a Martin, who she supposed was Martin Platt and thought he was going to be killed in a car crash. Overhearing Martin warning Ivy about panicking people with her spiritualism, Bet was overcome as her Martin had died in a car crash and the name Elizabeth was mentioned by Ivy's Medium. Bet then broke down and told her husband Alec Gilroy about Martin Downes.