The monster-party comedy “Office Christmas Party” follows a very common 1980s movie plotline, where an overly nasty authority figure lays down some ultimatum about closing some place and the workers have to reunite to raise the money to save it. Often accomplished through a carwash.

With “Office Christmas Party,” the villain is Jennifer Aniston’s Carol Vanstone, a heartless CEO of a tech company concerned only with the bottom line. She took over the role after her father died. Her fun-loving brother Clay (T.J. Miller) runs the firm’s Chicago office, with the help of his Chief Technical Officer Josh (Jason Bateman) and his No. 2 Tracey (Olivia Munn).

Special notice must be paid to Kate McKinnon as Mary a gassy, uptight woman who works in human resources, who spends the movie clad in a garish nondenominational sweater. She’s a scene stealer who makes everything she works on better.

The ultimatum comes down right before the holidays — if Clay’s office can’t hit some lofty goal, she’s shutting it down and everyone’s fired. And no Christmas party.

To save the office, Clay comes up with a plan, to throw a throwdown Christmas party, invite a big-money client (Courtney B. Vance) they’re courting and hope the event gets him to give them the account.

All this is just a set up for a raucous party with tons of booze, nasty behavior and inhibitions being thrown out the door.

Beyond the leads, “Office Christmas Party” is blessed with a wonderful ensemble cast of funny folks: Rob Corddry, Jillian Bell, Vanessa Bayer, Randall Park, Sam Richardson, Karan Soni and Da’Vine Joy Randolph.

Miller, a unique comedic voice (with a unique voice indeed), brings a gentle sincerity and honesty to Clay, who means well in everything he does. He’s a goofball, willing to sacrifice everything for the people he loves. And he brings a lot of heart of the film, which it needs as it devolves into chaos.

Aniston, who has fewer good movies than she has friends, gives another “Horrible Boss” performance here. With this and the cult-favorite “Office Space,” perhaps she should make more movies with the word “Office” in the title.

“Office Christmas Party” has a lot of funny moments, but it goes on for way too long, and it takes the debauchery about five steps too far.

But this cast is incredibly funny, and even when you’re bored by the party antics, another funny bit comes along.