Carrey, who plays vigilante Colonel Stars and Stripes in the sequel to the 2010 hit, has distanced himself from the film, saying the shooting massacre at Connecticut's Sandy Hook Elementary school changed his perspective.
Wadlow says Carrey is as unpredictable in real life as he is as an actor and "you never know what he is going to do or say."
He says he hopes people will see the movie and judge for themselves.
He says that in many ways the movie, which sees the return of Aaron Taylor-Johnson as Kick-Ass and Chloë Grace Moretz as Hit-Girl, is less violent than its predecessor, with more hand-to-hand combat and fewer guns.
Despite the controversy, Wadlow said on Tuesday that Carrey is "fantastic in the movie," and he'd work with him again.