There is a fine line between drama and melodrama, but “Imaginary Heroes” takes less than a half-hour to cross that line. The ensemble cast does what it can to keep the film grounded, but the script places so much tragedy on their plates that what should be a subtle but powerful film (a la “The Ice Storm), is instead converted into a soap opera.

Opening for a week this month before reopening in the more fiscally forgiving February, Dan Harris’s debut film, similar in tone to “American Beauty,” stars Emile Hirsch (“The Girl Next Door”) as Tim Travis, a high school senior who finds his dysfunctional suburban family (led by Sigourney Weaver and Jeff Daniels) coming apart after the suicide of his older brother (Kip Pardue).

Tim is not ‘the only normal one’ as is often the case for protagonists in such movies. He is emotionally damaged, the product of his house, and thus acts out in antisocial ways like the rest of his relatives. Mr. Hirsch, who has to carry the movie, is superb. Ms. Weaver and Mr. Daniels, both stuck in ugly roles, prove equal to the challenge.

But on the whole, Mr. Harris (who scripted as well) overextends himself. He subjects every calamity he can upon the Travises. He jams manufactured depression down the audience’s throat, not allowing it to develop naturally. Over the course of the film, the cast goes through two suicides; one suicide attempt; one car accident; one head smashed on a mirror; one oedipal complex; and one bout of homosexual incest.