William "Billy" Mayhew is the vicar at St. Mary's Church and works part time at For Your Fries Only. He is the ex-boyfriend of Sean Tully and was also in an on/off relationship with Todd Grimshaw and the guardian of Summer Spellman.
Billy met Sean Tully at a nightclub in December 2014. The pair got chatting and exchanged phone numbers. One week later, Sean invited him to 11 Coronation Street for dinner and to meet Eileen Grimshaw, her son Todd and Eileen's half-sister Julie Carp.
In April 2015, Billy and Sean went for a hike in the Peak District, after a mere four mile walk they decided to stop at a local pub for a meal and somewhere to spend the night. At the pub they were offered choices from the limited menu, one of which was hotpot and Billy enjoyed ribbing Sean that the pub's hotpot might be better than the one he served in the Rovers made to Betty Williams' handed-down recipe. They also asked the Landlord for a room for the night and were told that the only one available was a twin. Sean's comment to Billy about pushing the two beds together caused the landlord to give them a significant look as he asked for their names for the booking. After the pair finished their meal, the landlord told them that he actually didn't have any rooms left and gave the excuse that his wife had taken a phone booking that morning, but followed her usual habit of not writing it in the book. Sean and Billy smelled a rat and questioned the response but were told that he didn't have to explain himself. He added insult by injury by telling them that they could have their puddings but then they had to leave. Sean confronted the man with his bigotry by quoting the old boarding house notice of: "No blacks, no gays, no Irish" and told him to get into the twenty-first century. Billy also questioned if the man's stance was Christian but was told that he hated "God-botherers" more than he hated.. .but couldn't bring himself to finish the sentence. The pair accused him of cowardice as well as bigotry and left the pub. After the fiasco Julie informed the Weatherfield Gazette about the homophobic incident that had occurred.
The following month, Billy conducted Deirdre Barlow's funeral.
Billy's big break in Weatherfield came in January 2016, when Eva Price informed him that she was sceptical that her boss Aidan Connor's new business partners, Richie and Julia O'Driscoll, were keeping Marta Zarek, a Polish employee, as a slave in their home. Billy couldn't be too sure, so he and Eva went hunting for Marta when she was found to be hiding in the Underworld supply loft. Billy and Eva found Marta beneath an overpass, and they tried to question her on what was happening, but she ran away.
Eva later got critical evidence that the O'Driscolls really were keeping Marta prisoner when they were acting secretive about their private life. This convinced Eva to organise breaking into the house and finding out whether Marta really was being held as a slave. On an initial stakeout, Billy and Eva saw a figure who looked like Marta through a window, even though the O'Driscolls had told them that Marta had gone back to Poland.
The next day, Aidan was convinced that the O'Driscolls really were holding a captive, and agreed to help Billy and Eva. The pair broke in to the O'Driscolls' house as they were at a convention, and they found a door with a padlock on it. After searching, the pair found a key, unlocked the door, and found a cowering Marta, hunched in fear. They promised to help her, but Richie and Julia arrived home early from the convention, trapping the trio upstairs. They found Billy, Eva, and Marta, with Richie punching Billy, and holding Marta over a railing. Billy and Eva's saving grace came when Aidan arrived just in time and right-hooked Richie. Aidan had rushed over as Eva was not answering her phone, which had fallen out of her pocket in the car. Billy called the police, but they arrested all of them (excluding Marta) for various reasons, Richie and Julia for slavery, Aidan for assault, and Billy and Eva for burglary and criminal damage. Later however, Billy, Eva, and Aidan were all released without charge, and Marta returned to Poland.
In June 2017, Billy's ex, Drew Spellman, arrived and asked Billy if he could look after his daughter, Summer Spellman, after he dies. After a debate between Billy and Todd, they agreed to take care of Summer. Drew died the same month and, after a fight with Geraldine Spellman, Billy and Todd got the legal guardian rights for Summer and the three of them moved into 19a Rosamund Street.
In December 2017, Billy was stabbed in the leg by a sharp, metal four leaf clover he had in his pocket outside of court for punching Peter Barlow. Believing he was dying, Billy confessed to Peter that, in 2001, Billy had left Susan Barlow for dead after a crash. On Christmas Day, Billy fell over a cliff after Peter had threatened to throw him over it. Billy survived but when he woke up on boxing day he was informed by Eileen Grimshaw that Todd and Summer had gone on the run. Summer did return but alone, without Todd.
After Billy returned home, he was in a wheelchair so Summer had to look after him and do everything for him. Billy was also reliant on painkillers and Adam Barlow, Susan's son, fed Billy stronger painkillers as revenge, getting him addicted to them. As a result Billy contacted Lee and together they took heroin. Billy subsequently went on the run after getting hooked on drugs. In March 2018, Billy broke into No.11 for money but was caught by Peter who managed to make Billy admit to his addiction. Billy's Bishop, John Thornber, got Billy admitted to rehab.
First and last lines
"I've been here three weeks, this is my first time in the village" (First line, to Sean Tully)