All in all, this is a sloppy, unoriginal, brain-dead mess that can't even be bothered to get itself out of trouble.

What's even more depressing than the never-ending stream of sub-sixth-grade toilet humor is the sad fact that Year One is helmed and co-produced by two of the best laughmeisters in the business.

Creatively it's a giant step backwards, with Jack Black and Michael Cera playing to the kids as inept hunter-gatherers who stumble across various Old Testament characters.

A dreary, groan-inducing comedy that fails to be funny or entertaining under even the most lenient terms.