Francois Ozon’s “Swimming Pool” is one of those rare films that can pull off scenes of comedy, suspense and drama. Unfortunately, not every scene works, and the film squanders whatever potential it had to tackle serious issues. But thanks to the lead performances of Charlotte Rampling and Ludivine Sagnier, it is at least entertaining.

Sarah Morton (Rampling) is an aging British mystery writer who is all out of ideas. Her publisher offers her his summer house in France, and Sarah accepts. She hopes the change in environment will help her find inspiration. Once she arrives at the beautiful house, surrounded by peace and quiet, the words begin to flow. Sarah writes in the morning and spends her afternoons in a local cafe where she exchanges flirtatious glances with a much younger waiter (all the while maintaining her prim and proper manners).

Amidst this perfection enters the young and beautiful Julie (Sagnier), the publisher’s estranged daughter. The two instantly dislike each other, and this — the first stage of their relationship — is where the film is at its humorous best. Ozon excels at creating awkward situations as the women adjust to each other’s disparate lifestyles. Sarah likes her house quiet; Julie likes company and quickly fills the house with men and loud music. In an especially comic scene, we see that the men Julie brings home are not young and handsome as expected, but old, fat, bald and, on occasion, clad in incredibly skimpy underwear.

Although she appears to be repulsed, Sarah is morbidly fascinated by Julie and her guests. Seeing in Julie the possibility of a new book, she begins to take peeks at Julie’s diary, and then one night asks Julie to go to dinner. As the two drink and talk, Julie tells Sarah of her troubled relationship with her mother and her father (Sarah’s publisher). The film falters here a little; the revelations about Julie do not seem as surprising or horrible as they are meant to be. Still, the performances of Sagnier and Rampling are impressive — they handle the drama as deftly as they do the comedy. The chemistry between the two women is undeniable during these scenes of female bonding.

The film takes its next twist when Julie brings home the waiter with whom Sarah had flirted earlier. Julie quickly sees the attraction between the two. Jealous, she tries to seduce the waiter, but he refuses. The next morning Sarah discovers the waiter is missing; he has not reported to work, nor has he been seen at his house. The film moves into a kind of investigative phase as Sarah the mystery writer takes part in her own mystery, trying to find the waiter. Here the film falls apart; only Rampling’s performance keeps the film from becoming an episode of “Murder, She Wrote.” Most of the clues she finds mean nothing and are never explained, as if they are only filler material to lengthen this part of the film.

Ultimately, the mystery is all wrapped up, or seemingly so anyway — at the last minute, Ozon wallops us over the head with one last twist. In these final moments everything that has come before is called into question; the viewer is forced to think back over what has happened in the film to try to make sense of it. This might be a good thing if thinking back over the story revealed certain continuous themes or ideas that were worth pondering, but unfortunately there are no such connections. Certain scenes of suspense are done quite well, but there is not enough to make this a real mystery film, nor is there quite enough humor to make this a comedy. The plot is thin and tries to hint at layers that are not quite there. Still, the film is engaging as a character study of the two women, and their performances are enrapturing, making “Swimming Pool” an overall satisfying, if not meaningful, film.