Callum and Kylie shared a brief relationship in 2006 before and after Max's birth, but Kylie lost contact when Callum was imprisoned. When he came back into her life eight years later, he attempted to get custody of Max, using both legal and underhand methods to do so. His reign of terror ended when Kylie killed him as he was assaulting Sarah Platt.
After his death, Callum's body was buried under 8 Coronation Street's annex by Kylie and David, where it lay for amost a year. The murder was ultimately blamed on the late Tony Stewart after the manhole covering Callum's body collapsed in 2016.
Nearly six months after his death, Sarah gave birth to his son, Harry.
Callum and Kylie grew up on the Paul Robeson Estate in Wythenshawe, and started a relationship around 2005. When Kylie became pregnant with their son Max, she was kicked out by her father Brian resulting in her reliance on Callum. He became a little less supportive as the pregnancy progressed, but returned to Kylie when Max was born. Callum later ended up in prison after assaulting a judge, and lost contact with his partner and child.
After Kylie married David Platt, who would become a father figure to Max, she didn't speak about her past. However in 2014, she opened up about Callum when Max was suspected of having ADHD and the possibility of it being a hereditary illness. When asked what became of Callum after he was sent to prison, Kylie was uncertain and unsure whether he would have behaved himself inside.
Feeling the stress of family life, Kylie headed back to her old haunt - The Dog & Gun - and met Callum for the first time in eight years. She looked to score speed from him, which he happily supplied and hoped to woo her back to her old life, trying to convince her that family life and being married to David was not exciting enough for her. However Kylie only wanted Callum to give her drugs and nothing more.
Callum started to integrate himself into Max's life and on Christmas Day, he turned up at No.8 while the rest of the Platt family were celebrating David's birthday at Just Nick's, bringing a bike for his son. David returned home unannounced and was shocked to find that not only that he was Kylie's dealer, but Max's biological father. The pair got into a scuffle, and Callum left when the rest of the family returned. Angry with Kylie for lying to him, David kicked her out of the house and she was picked up by Callum.
In the new year, Callum was confronted by a worried David asking where Kylie was, however he denied all knowledge of her whereabouts. Believing that he was lying, David and a reluctant Eva Price broke into Callum's flat to search for Kylie, but found he was telling the truth. Callum warned David off and he tried to get back at him by reporting his drug dealing, but Callum was one step ahead and cleared his flat of any sign of drugs paraphernalia before the police arrived.
Callum began turning up more frequently, bothering David and wanting to see Max. He soon got acquainted with Katy Armstrong and they started dating, despite David warning her that Callum was a drug dealer. Callum later revealed to Max that he was his real dad, which caused the boy to rebel against David and wanted to know more about his real father. David eventually gave in and told Callum that he would be able to see Max.
Callum broke up with Katy after mocking her for her lack of ambition after she revealed to him she wanted to remain in Weatherfield with him rather than leave for a new life in Portugal with her mother Linda Hancock. Callum then set his sights on David's sister Sarah who'd returned after spending seven years in Milan. Although Sarah saw through Callum's act, she fell for his charms and they soon slept together.
David attempted to have Callum locked up, and blackmailed Andy Carver to plant drugs in Callum's car. Callum caught Andy and held him prisoner in the back room of the pub, but David arrived to tell him it was his idea. David was taken to an abandoned warehouse where Callum gave him a beating with a baseball bat. With his plan a failure, the last straw for David was discovering Callum and Sarah's relationship. He fled with an unwilling Max, but Callum tracked him down to Liverpool when Max called him on his mobile.
Kylie eventually returned to David and was shocked to find that, through above-board legal means, Callum had gained partial custody of his son with the intention of gaining full parental rights. Max later found a gun in his bedroom at Callum's flat, causing Sarah to see Callum's true colours and they split up. When Jason Grimshaw stood up to Callum for harassing Sarah and her daughter Bethany, he was attacked by Callum and his heavies and ended up in Weatherfield General. Unbeknown to Callum, Max had witnessed the attack and grew to fear his father and refused to be with him. Once Jason's father, Tony Stewart, discovered who had beaten his son, he found Callum and gave him a beating in return, although the intervention of Liz McDonald stopped Tony from going too far with his revenge.
In September 2015, Callum was under pressure to pay off a £20,000 debt to drug dealer Denton and tried to extort the money from the Platts in return for relinquishing his rights to Max. He began to harass the family and threatened them with violence unless they got him the money. Events reached a climax when Sarah tried unsuccessfully to record Callum talking about his misdeeds. He then pinned her down to the ground and forced himself on top of her, with the intention of raping her inside No.8. She was saved by Kylie who killed the thug with a blow from a wrench to the head. David, Kylie and Sarah planned to dump the body in Weatherfield Canal but fate was against them and they were forced to secrete the corpse in a manhole under their garage which was being converted into a granny annex for Gail Rodwell.
The secret of Callum's death, and the location of his body, remained a secret known only to David, Kylie and Sarah for eight months, with the three of them dealing with the matter with varying degrees of composure. On the night of Nick Tilsley's wedding to Carla Connor in May 2016, the hiding place was discovered when Tyrone Dobbs crashed his pick-up truck through the front of the annex. The weight of vehicle cracked the flimsy concrete covering the manhole, breaking it open. The stench of the decomposing body left no doubt in David's mind that discovery was imminent and it was indeed only a matter of hours before builders made the discovery and alerted the police. A credit card on the corpse gave its identity away and a murder investigation began.
Following Callum's murder and subsequent cover-up several characters came to learn the truth. In August 2016, Todd Grimshaw believed that Sarah had murdered Callum and lied to the police for her. However, Sarah was able to convince him of her innocence and therefore Todd began to suspect David. The police soon learned of Tony Stewart's grievance with Callum, and the fact that he was the builder who had converted the annex, and identified him as the killer. Wanting to prove Tony innocent, due to the fact that his brother Jason had started drinking heavily as a result of Tony's supposed guilt, Todd planned to report David to the police, but eventually decided against it when he learned that that Kylie had been the killer.
In June 2018, Sarah confessed to covering up Callum's murder as she tried to convince Gary Windass not to take ultimate revenge on serial killer Pat Phelan. Later in January 2019, Sarah also let slip the secret to her brother Nick Tilsley and he used the information to blackmail David into keeping quiet about Nick having stolen their gran Audrey Roberts's money.
The character was introduced on a temporary basis in order to tie with the exit of Kylie Platt as Paula Lane was going on maternity leave, but as actor Sean Ward impressed bosses, he was promoted to a regular with his contract extended into 2015.
Sean Ward's final episode (in broadcast order), Episode 8740 (23rd September 2015), was broadcast live to celebrate 60 years of ITV. In the episode, Callum was murdered by Kylie as she defended sister-in-law Sarah Platt. The manner of Ward's exit from the show wasn't publicised before the broadcast.
First and last lines
"That is a big mistake, you stupid, stupid girl! You stupid girl!" (Final line, to Sarah Platt)