The story is about Lloyd and Harold (Jim Carrey and Jeff Daniels)--two complete idiots who are roommates. When a passenger in Lloyd's limo leaves a briefcase behind, he vows to return it to her. There are two huge problems with this. First, this occurred in Rhode Island and she now is in Aspen! Second, although Lloyd thought she left it by accident, it was ransom money...and now he and Harold have it and mobsters are after them!
Much of the humor was stupid--the sort of stuff middle school kids would love. However, I must admit that although much of the humor was awful, sometime is still made me laugh. Plus, the film ended well. So, I do recommend it BUT must point out that it is NOT for anyone wanting cleverness. Nope...crude humor, bad jokes and embarrassing moments...that's what you'll find and you, too, might laugh a bit like I did.
By the way, for the love of God, do NOT watch the sequel "Dumb and Dumberer". None of the original writers, directors or actors are in it and it is a total bomb....and currently is on IMDB's notorious Bottom 100 list.