Will Ferrell and John C. Reilly in Step BrothersSTEP BROTHERS

As I see it, the only way you can remotely enjoy director Adam McKay's Step Brothers is by accepting that all of the characters in it, even the seemingly levelheaded ones, are out of their minds. And even then you might not enjoy it.

Mark Ruffalo and Jennifer Garner in 13 Going on 3013 GOING ON 30

When you watch a body-switching comedy such as Big or Freaky Friday, you know immediately that the movie is going to require a huge suspension of disbelief; these are comedy fantasies, after all, and bitching about logic and realistic plotting is the surest way to kill your good time.

David Duchovny, Julianne Moore, Seann William Scott, and Orlando Jones in EvolutionEVOLUTION

The sci-fi comedy Evolution is like Ghostbusters without Bill Murray, which isn't surprising since both films were directed by Ivan Reitman, but it also means that it's like Ghostbusters without the big laughs. In that 1984 blockbuster, Murray delivered his lines with an italicized innuendo that made even his throwaway quips hilarious; without his presence, the film (and its underrated 1989 follow-up) would just have been a moderately pleasant, cheesy, overscaled, haphazardly paced affair. That's Evolution.