The actor's villainous character will be found dead next week, leaving viewers to wonder who was responsible.
Coronation Street bosses have named Carla, Kevin, Michelle, Peter and Sally as the main five characters who will become police suspects in the case.
Lancel today told BBC Breakfast: "Frank's made a lot of enemies on the street for a lot of different reasons. He's been monstrous, horrendous. People know what he's done - he's assaulted and twisted the knife into many people, and he's closed down the factory, so there's plenty of people who could be bumping off Frank and there are many suspects."
He continued: "Frank dies, but who did it and why? You've got Michelle Connor - Frank has basically ruined her working life. You've got Peter Barlow - Frank is responsible for him getting back on the bottle, and Frank assaulted his beloved Carla Connor. With Carla, Frank has ruined and destroyed her life - and got away with it.
"Kevin Webster, who was married to Sally Webster, is discovering what this monster can do to Sally. And Sally has given her heart to this man and he's broken it in two. So they're all possible - all of them."
Lancel said that he is looking forward to watching Coronation Street "as a punter" in the coming weeks as the aftermath of Frank's death plays out.
"With the way it was shot, it could be anybody," he added. "You don't actually see who does it, so it's classic Coronation Street. It's an amazing place, because whatever happens on the street, whether it's something horrendous like this or something comedic, it always goes back to those cobbles."
Coronation Street airs Frank's final episodes on Monday, March 5 at 7.30pm and 8.30pm on ITV1.
> Coronation Street confirms Frank Foster death plot
> Coronation Street confirms five Frank murder suspects
> Coronation Street Alison King: 'Carla easily capable of killing Frank'
> Coronation Street Sally Dynevor interview: 'Sally will be terrified'
> Read more Coronation Street spoilers and news
Watch a preview of tonight's (March 2) Coronation Street double bill in the video below: