Sneak peek: T.J. Miller gets wild in 'Office Christmas Party'

T.J. Miller can't recall ever having any crazy holiday work shindigs, though the actor does remember kegs, cake and the resulting sick stomach from Friday ragers when he was a legal secretary in Chicago.

“Frosting and beer can be a very fun but lethal combination starting at around midnight,” says Miller, star of the upcoming ensemble comedy Office Christmas Party (in theaters Dec. 9).

Drugs, alcohol and bad decisions are all on tap in the movie, directed by Will Speck and Josh Gordon (Blades of Glory). Miller plays Clay Vanstone, the warmhearted president of a struggling branch of a tech company. The CEO happens to be his ruthless sister Carol (Jennifer Aniston), who is threatening to lay off all of Clay’s employees.

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Their father, who founded the family business, recently died, so power is up for grabs. To land a big client — as well as save the jobs of his employees and let off some steam — Clay teams with his right-hand man and chief technical officer Josh (Jason Bateman) to throw a blowout that would impress even Santa.

“When you spend such a large portion of your life working — and it’s not fun, and you’re worried about getting sued or fired for saying the wrong thing or for acting crazy at a work party — then what has work done to America?” Miller asks. “That’s the impetus to have a huge office Christmas party.”

Lots of hijinks ensue. In one scene, Miller wears a bear head and paws (“I fought hard for it, and in the end, we won out,” the actor says) and the employees get into “some trouble that pulls them out into a dangerous night of snowy Chicago during a blizzard,” says Speck.

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Aniston is “a human delight,” Miller says, and while her character puts profit over people, “as with any great major motion picture, everybody’s relationship changes over the course of the film.”

Unlike his Silicon Valley persona, Miller’s Clay is "a person you love and want to follow,” says Gordon. While there's some of the absurdist comedy that Miller has done in the past, “he also has a lot of heart and vulnerability and humanity that we hope sort of surprise people,” Speck adds.

The supporting cast features “an amazing bench” of actors, Speck reports: Olivia Munn co-stars as a talented engineer, Sam Richardson is a guy from legal who has a secret life as a DJ, Vanessa Bayer plays an executive assistant using the party to find a boyfriend, Rob Corddry is the very disgruntled head of customer service, and Kate McKinnon is a holiday-obsessed human resources staffer. (Speck promises that it's the breakout Ghostbusters star's "next step in her climb toward world domination.”)

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The personalities and situations are relatable in that there are “universal truths” to office Christmas parties, Speck says, “and it doesn’t matter if you’re working at a very small car-rental office in Albuquerque or a giant tower corporation in New York City.”

Adds Gordon: “We weren't short of people coming to us with stories.”