“Best Man Down” is now streaming on VOD and is available for purchase on ITunes. PG-13, 1:31, two stars out of four.

When your film’s most compelling character dies in the first five minutes, your film has a problem. Writer-director Ted Koland’s debut comedy-drama “Best Man Down” has that problem. And a few others.

Lumpy (Tyler Labine) is a screw-up in the first-act-of-a-Jack-Black-movie mode. The best man for his friend Scott (Justin Long) at his wedding to Kristin (Jess Weixler), we see him at the Arizona reception, pounding shots, staggering around the dance floor, staining the bride’s dress. He’s bad news — well-meaning bad news, but bad news.

But he looks like a lot of fun, until a rather poignant scene where Lumpy wakes up, alone, and staggers around his room in a drunken, fearful haze. It’s a sadly revealing moment of the depths of Lumpy’s loneliness beneath his boozy exterior, and the viewer hopes it might be the bottom he needs to hit to finally get his life together.

Instead, he wanders outside the hotel, falls on a cactus, and dies. Exit Lumpy.

So it’s up to Scott and Kristin to ferry his body back to their hometown of Minneapolis and make funeral arrangements. Right away, the tone of the movie seems off, veering into inappropriately wacky comedy (Kristin unzips Lumpy’s body bag to check out his junk? Really?) and pathos, as Scott realizes he never really knew his best friend. As they break the news to family and friends, they find out that Lumpy was some kind of secret Good Samaritan to the people around him.

Meanwhile, there’s a completely different plotline going on about a 15-year-old girl named Ramsey (Addison Timlin), who lives with a trailer-trash mother (Frances O’Connor) and her cartoonish meth-dealer boyfriend (Evan Jones). Not only do we not learn what connection Ramsey has to Lumpy until we’re well into “Best Man Down,” but the Midwestern miserablist tone of these scenes is completely different than the broad comedy of the Scott-Kristin storyline. Koland cuts back and forth between the two, like they’re two movies he couldn’t quite finish and decided to graft one onto the other and see what happened.

It’s kind of a mess — the only one who really makes an impression in the cast is Labine, who in that opening scene and a couple of flashbacks, brings a messed-up soulfulness to Lumpy that’s worth exploring. But of course, there’s no need to give him a redemptive arc. Because he’s dead.