Rashida Jones and Andy Samberg play the title roles in the comedy "Celeste & Jesse Forever." Courtesy Sony Pictures Classics

Labor Day weekend is traditionally one of the weakest in terms of movie releases, with Hollywood assuming that most people want to catch one more weekend of outdoor activity before the summer’s end.

The only studio film opening today is “The Possession,” a Jewish take on “The Exorcist” that was not screened for Utah critics. Meanwhile, Disney is using the three-day weekend to bring both “The Avengers” and “Brave” back to more theaters for another dip at the box office.

The art-house slate is fairly full this weekend. The best of that lot is “Celeste & Jesse Forever,” a smart, thoughtful and funny romantic comedy starring Rashida Jones (who co-wrote it) and Andy Samberg as a separated couple who can’t quite get the “separated” part right. They still hang out together, raising questions about whether they should stay married. But then Jesse makes a bombshell announcement, leaving Celeste adrift in the dating world. Jones creates a strong character for herself, a tough cookie crumbling as she realizes that being the smartest person in the room can be lonely.

“Robot & Frank,” which was the Salt Lake City opening film at this year’s Sundance Film Festival, is whimsical almost to a fault. It centers on a retiree (Frank Langella) in the early stages of Alzheimer’s. His son (James Marsden) buys him a helper robot (this is the near future), who goes from tending to Frank’s medications to becoming his accomplice when Frank decides to take up his old job -- as a jewel thief. The sentimental story is bolstered by Langella’s sharp performance, and by the realistic depiction of the robot (by dance Rachael Ma and voice actor Peter Sarsgaard).

“Killer Joe” is a tough movie to watch, an NC-17 wallow in brutal violence, rough sexuality and a distasteful set of white-trash characters plotting a murder. The movie reteams director William Friedkin (“The Exorcist”) and playwright Tracy Letts, who worked together on the claustrophobic thriller “Bug”.” This movie isn’t nearly as interesting, but what’s good about it is Matthew McConaughey, giving a fiercely controlled performance as a cop-turned-contract killer.

Over at the Cinemark 24 at Jordan Landing, there’s a cool little ghost story, “The Awakening.” It’s set in England 1921, and centers on a debunker of the supernatural (played by Rebecca Hall) who’s called in to investigate a boarding school where something’s going bump in the night. This one has some chilling atmospherics that almost compensate for an ending that falls apart.

There also are two holdovers that opened Wednesday: The engrossing gangster drama “Lawless,” and the awful kiddie movie “The Oogieloves in the Big Balloon Adventure.”