Last week’s release of “The Dark Knight” marked the peak of the summer box office, with record-breaking receipts for the latest Batman adventure. While that action blockbuster is certainly a hard act to follow, two new flicks will try to compete, each with something different to offer.

Will Ferrell takes a stab at a movie whose low-concept inspiration seems to be of the “Dumb and Dumber” variety. John C. Reilly (“Walk Hard: The Dewey Cox Story”) is the Jeff Daniels to Ferrell’s Jim Carrey in “Step Brothers.”

Ferrell’s funnyordie.com co-creator and former “SNL” writer Adam McKay is the co-writer (with Ferrell) and director of this silly comedy, which is not a far cry from some of the other movies on his résumé.

McKay also wrote and directed Ferrell’s popular comedies “Anchorman: The Legend of Ron Burgundy” and “Talladega Nights: The Ballad of Ricky Bobby,” which also featured Reilly as Ferrell’s profoundly idiotic best friend.

For Ferrell, whose popularity has waned slightly after disappointing turns in the asinine sports spoofs “Blades of Glory” and “Semi-Pro,” playing a grown man who acts like an irritating, naïve child comes naturally. After all, he did it so well in “Elf.”

As she did in that movie, Mary Steenburgen plays Ferrell’s mother figure in this film, and, no, she’s not that much older than him, which seems to be part of the joke. Ferrell and Reilly play similarly immature middle-aged men who still live with their parents. Initially, there is some friction between the two characters as they become stepbrothers and are forced to live in the same house.

Yet, with so many slacker low-life qualities in common, the two were bound to become the best of friends. Their natural ability to feed each other’s childish tendencies comes to the dismay of their parents, who would really love to see their loser sons get jobs and get out of the house for good.

Look for a cameo appearance by Seth Rogen (“Knocked Up”), as Ferrell and McKay belong to the “Friends of Judd Apatow” club, along with the comically unattractive Rogen. Power producer Apatow helped out with this flick, too.

This week’s other opener is a spooky new chapter in the popular sci-fi television drama “The X Files.” Fans of the series, which ran from 1993 to 2002, will be happy to see David Duchovny and Gillian Anderson reunited as FBI Agents Fox Mulder and Dana Scully.

The show’s creator, Chris Carter, wrote and directed “The X-Files: I Want to Believe,” which borrows a saying from a poster in Mulder’s office. The paranormal investigators try to solve a creepy mystery in a snowy town while coping with their awkward past romance.

While fans of the show will enjoy this nostalgic reunion of sorts, Carter claims the film will appeal to folks who have never seen the show nor had the pleasure of seeing Scully do an alien autopsy.

Audiences have enjoyed Golden Globe winner Duchovny recently in Showtime’s “Californication,” while Anderson has been away from the American media, living and acting primarily in England. Amanda Peet and rapper Xzibit also star in this second “X Files” feature film. The first was a mildly successful 1998 release.

Movie Buzz is a column by Mariah Gardner. It appears in The Metro Spirit each Wednesday.