I'm certain that we're not getting an Ace Ventura from Carrey-- I don't even remember the last time he did that schtick, to be quite honest with you (even his lousy recent comedies he hasn't done).  If he's meant to be funny, I hope it's like his turn as Andy Kaufman where he's funny but only to him and it's disturbing to everyone else, like he's thinking on a different wavelength, like the Joker (bear in mind I know NOTHING about this character).