As I said before in my Me, Myself & Irene review I'm not a fan of Jim Carrey and Ace Ventura: Pet Detective is better then MM&I but still pretty boring.
Jim Carrey plays Ace Ventura: Pet Detective, a guy that specializes in finding lost/missing/petnaped pets and returning them back to their owners.
The major story of the movie is the kidnapping of Miami Dolphins mascot dolphin, Snowflake, and Ace goes on to find it while uncovering a bigger plot that includes Dan Marino.
While Carrey is a bit funnier then MM&I he is still boring and mostly unfunny and supporting cast doesn't help the movie either.
Writing is a bit of a saving grace as some of the dialog is witty and most of situations are well used but Carrey acting killed most of it.
Overall Ace Ventura: Pet Detective is a pretty average comedy that could have been really funny but wasn't due to bad acting.