Fans of "The Office" know Ed Helms as the lovable if over-eager and occasionally erratic Andy Bernard. Fans of "The Hangover" movies know Helms as Dr. Stu Price, the dentist who loses a tooth during a rollicking guys' trip to Vegas.

Helms' character in his new movie, "Jeff, Who Lives at Home," is quite a departure. He lacks Andy's charm and Stu's bromantic likability. In the movie co-starring Jason Segel as Jeff (who does in fact live at home), Helms is Pat, a self-important boor. He's the kind of guy who plans "business lunches" at Hooter's, and who springs a new Porsche on his wife just as she is fretting about their finances.

"When I first picked up the script I did not like Pat," Helms told us during a recent interview. "I wasn’t interested in portraying Pat. By the time I got to the end of the script I was so thrilled and excited by this character. As reprehensible as he is, he’s very complicated."

The movie -- also starring Judy Greer as Pat's long-suffering wife and Susan Sarandon as Pat and Jeff's even longer-suffering mom --  opened Friday at the Landmark Midtown, Lefont Sandy Springs, AMC Mansell Crossing and AMC Phipps Plaza theaters.

Written and directed by filmmaking brothers Jay and Mark Duplass, the story is set in Baton Rouge. Filming took place in and around New Orleans, but the cameras managed to feature only the most generic and charmless locations, beginning with Jeff's mom's outdated basement.

"It does challenge viewers a little bit more," Helms said. "If you see ‘Jason Segel and Ed Helms' it conjures something very specific. That’s just not what this is. This is not a bonanza. It’s something different and very surprising."

The plot meanders from the couch where Jeff spends most of his time and follows him around town (by bus, at first, as the 30-year-old apparently lacks his own wheels and maybe even a license), driven by what he and only he thinks is some mystical mission. Sarandon, a widowed mom of two rather disappointing adult sons whose scenes mostly take place in her dreary office, manages to light up the grim office cubicle farm whenever the camera finds her.

"I was very anxious to meet her," Helms said. "I was starstruck those first few minutes but she instantly put me at ease.  She’s so hilarious, sweet.  She’s elegant but down to earth."

Helms, an Atlanta native and Westminster Schools alum, was here for a private talk and reception at his alma mater in December.

"It was great to be back on campus," he said. "To see how it’s changed and how it’s stayed the same, share my experiences and encourage them to stay out of show business."

We asked if he knew anyone with the potential to become like Jeff during his formative years.

"I think we all know Jeffs," he said with a chuckle. "Maybe there’s a part in all of us that’s afraid there’s more of Jeff than we might like."