Davis, who starred in Ricky Gervais comedy Life’s Too Short, and Dennis, best know for Family Fortunes, are being lined up for the roles of King Arthur and his loyal servant Patsy.
It’s understood that Dennis will join the show next month, with Davis joining him from September.
The “lovingly ripped off” Monty Python musical is currently running at the Playhouse Theatre, following a national tour and a sting at the Harold Pinter.
Telling the story of King Arthur and the quest for the Holy Grail, the cast currently features Joe Pasquale as King Arthur and Bonnie Langford as The Lady of the Lake.
Dennis recently tweeted Langford saying he was “looking forward” to working with her.
The role of King Arthur has a long association with celebrity casting. Recent incumbents include Stephen Tompkinson, Jon Culshaw and Marcus Brigstocke.
The role of Patsy, which has previously been played by EastEnders’ Todd Carty, among others, will mark Warwick Davis’ West End debut. His film credits include Harry Potter, Willow and Hitchhiker’s Guide to the Galaxy.
Les Dennis has previously appeared in the West End in Chicago, Me and My Girl and Eurovision spoof musical Eurobeat. He has also starred in touring productions of High School Musical and Legally Blonde.
See also: Bonnie Langford stars in Spamalot’s Duck Sauce remake