Michael Gabriel "Mike" Ritchie (previously Ricci) was a US Air Force serviceman and old flame of Maggie Clegg's who stopped by Weatherfield on his way home after leaving the service in 1973.
Mike's surname had been Ricci until it was anglicised by his father. During World War II, he was stationed in Burtonwood along with GIs Steve Tanner and Gregg Flint, who he joined on their off-duty jaunts to Weatherfield. While Steve courted the glamorous Elsie Tanner, Mike pursued demure Maggie Preston, as did one of the other sergeants. Secretly dating Mike, Maggie went to the camp to see him leading everyone to assume that she was going out with the other man. Mike also knew Len Fairclough, who at this time was serving with the Royal Navy.
Mike never married; he carried a torch for a woman in Wichita but was turned down in favour of his friend Buck in 1955. After Buck died in Vietnam, Mike wrote to the woman and told him how he felt about her, prepared to return to the States if she said "yes". As he was leaving the service either way, Mike decided to look up old friends while in the UK, including Maggie, who now ran the Corner Shop in Coronation Street. Maggie and her assistant Norma Ford were confused when a telegram was received saying that "lover boy" was arriving, leading Norma to speculate on the identity of the sender. When Mike arrived at the shop, Maggie recognised him straight-away and received him with a warm embrace. Due to prior arrangements with Alf Roberts, Maggie couldn't see Mike that evening and so Mike made plans to remain in the area for a few days, staying at the Rovers Return.
With nothing to do for the evening, Mike went where the action was, gatecrashing Billy Walker and Alan Howard's party at 11 Coronation Street, along with Rita Littlewood and Ray Langton. Mike ended up sleeping on the back room floor and in the morning helped Alan tidy the place in time for Elsie getting home. Elsie rumbled Alan when Deirdre Hunt walked downstairs in her underclothes, having crashed out on Lucille Hewitt's bed. Mike left Alan to explain the sight to his wife, although he told Elsie the truth when Maggie requested that he do so in exchange for going to lunch with him.
Afterwards, Elsie had Mike and Maggie over for supper, leading the neighbours to gossip about the pair. Jealous of Mike and Maggie, Alf got at Mike over life in the USA and his country's late entry into the war, although Mike didn't take the bait. He didn't tell Maggie about the widow in Wichita but revealed that he might not be returning to America, leading Maggie to wonder if he was thinking of staying behind for her. Shortly thereafter, Mike received the letter he was waiting for, confirming that the widow in the States wanted him back. He then returned home, telling Maggie only that he was going there alone. Not knowing about the widow, Maggie wondered what had put him off and blamed Alf.
- The character's full name was given as "Michael G. Richey" on the letter from Wichita, seen in Episode 1276, but he was credited in all six episodes as "Mike Ritchie".