The actor joins the ITV soap next week as Michael Rodwell, an intruder who breaks into the Platt family's home and is disturbed by Kylie and Gail.
Michael initially appears on screen for two episodes which focus on the break-in and his subsequent getaway attempt.
The wayward character will then return on a more permanent basis from June, when Coronation Street kicks off a restorative justice storyline which will run across the summer.
As Gail is left deeply shaken by the incident at her home, she ends up meeting Michael again as part of the restorative justice process.
Against the odds, an unlikely friendship forms between the pair - much to the dismay of Gail's family.
Speaking of the upcoming storyline, Dennis explained: "Michael isn't a career burglar - he just thinks that the Platts' house is empty, so nobody will get hurt as they'll be insured. But it all goes wrong when Gail interrupts him and she's left quite frightened by the experience.
"Later on, Michael has the chance to apologise to Gail. After that, maybe the Platt family will be thinking that Gail has chosen badly again - even in the friendship stakes!"
The former Family Fortunes host filmed his first Coronation Street scenes in January and is now busy touring the UK in the Peter James play The Perfect Murder. He will return to filming at the Weatherfield soap in April.
Dennis's character was originally announced as Michael Rogers, but the surname was later changed to Rodwell.
Coronation Street airs Michael's dramatic debut on Monday, March 24 at 7.30pm and 8.30pm on ITV.
Read Les Dennis's first full Q&A about his Coronation Street role
Read our full spoilers for next week's Coronation Street episodes
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