The first thing everyone seems to mention about Serious Moonlight is that its screenplay is the last one written by the late Adrienne Shelly. Actress Cheryl Hines, who had a role in Shelly's film Waitress, is making her feature directorial debut with the dark comedy, which stars Meg Ryan and Timothy Hutton. The movie opened Austin Film Festival this year. It sounds like a sure-fire comedy, but unfortunately it just left me with a headache.

Serious Moonlight focuses on a married couple, Louise (Meg Ryan) and Ian (Timothy Hutton), who are supposed to meet in their country house for a rendezvous, but both arrive a day early. Louise wants to surprise her husband, but finds out that he also has a surprise: he's leaving her. She refuses to accept this, and ends up cracking him on the head with a vase, binding him with duct tape, and refusing to let him loose until he comes to his senses and realizes how much he loves her and wants to stay with her.

The premise could actually work -- it sounds a bit like one of those darkly loony Seventies comedies, or perhaps an early Pedro Almodovar film. However, the bitter humor that sustains those comedies is nowhere to be found in Serious Moonlight. Instead, we must endure heavy-handed dialogue, grating characters and a lot of shouting. I fought a serious temptation to leave the theater, especially during the first half of the movie. Fortunately, more characters appear in the second half to provide some relief: Kristen Bell as the young woman Ian has become enamored with, and Justin Long as a lawn-service guy who has hidden depths. The gimmicky ending is supposed to explain a lot of the confusing behavior earlier in the film, but you can't rely on a cute twist to save an entire movie.

I think that one problem is with the screenplay. From interviews with Hines, I gather that no one felt like they should change Shelly's script at all -- that they wanted to preserve her project exactly as she intended it. But words that might have seemed great on the page sound unnatural coming out of the actors' mouths -- too long, too bookish. Surely Shelly would have realized this in production and reshaped or cut some of the lines. Most of the action takes place in a single location -- the country house -- and it feels and sounds more like a stage play than a movie. In fact, with the right cast, Serious Moonlight probably would make a good play.

Casting is the other downfall of Serious Moonlight. Timothy Hutton is sympathetic even when he's enraged, believable, and fun to watch. Kristen Bell isn't bad as the Other Woman, but she's capable of much better roles than this featherweight mistress. And then there's Meg Ryan, who is painfully wrong as Louise. It was impossible for me to believe Louise capable of the kind of erratic mood swing that leads a previously sane woman to tie up her husband and tell him he can't leave until he loves her again, and I couldn't understand or sympathize. Frances McDormand or Holly Hunter could get away with it, easily; Cheryl Hines herself would have been a good choice. But Ryan's shiny happy face seems incapable of shadowy or subtle expressions -- her character burbles along inanely until you hope Ian runs off with somebody, anybody, even Justin Long's character.

I was disappointed in Serious Moonlight. I liked Waitress a lot and hoped to enjoy a repeat success for Adrienne Shelly's writing. Unfortunately, this movie simply doesn't work -- it's a comedy that didn't make me laugh.