The body-switching genre goes back at least to the 1882 novel Vice Versa (which was adapted as a 1988 movie starring Judge Reinhold and Fred Savage), and The Change-Up doesn’t bring anything new to it. The two people switching bodies here aren’t even all that different: Best friends Dave (Jason Bateman) and Mitch (Ryan Reynolds) are the same age, come from similar backgrounds and could practically be brothers, although Dave is a settled family man while Mitch is an irresponsible slacker and womanizer. So they inadvertently wish to take over each other’s lives, with predictable results. The filmmakers dial the crude humor way up, but it doesn’t make up for the contrived plotting or the moronic characters, and it isn’t particularly funny, either. This movie features a baby taking a crap in a character’s mouth and heartfelt speeches about the importance of family, neither of which it can pull off successfully.