If you were an employee at Kendrick Industries (in the Whitney Towers) in the middle of the 1970's, there was one night you couldn't wait for. The annual Christmas Eve party and all the booze you could drink up there on the 40th floor(a bonus feature was the impressive city view).
Of course your fellow employees had other things on their mind and mainly it was sex and a little afterparty.
Before the flow of booze ended and the bonuses were handed out, Betty Carson (Kelly Jean Peters) and her friend Ginger Macklin (Laurie Heineman) are in an office where Betty is arguing with her mother. She tells her that she's entitled to some fun and she plans on being out for a little longer, because she wants to get her claws into Kelly Freeman (Don Meredith). By hooking up with him, this single mother thinks all of her dreams will come true.
Ginger really doesn't feel like staying behind, but Betty talks her into staying and the three of them head off into Dan Overland's (John Forsythe) office. They don't know that he's sitting in the dark drinking, but invites them in.
Soon after, Howard Foster (Joseph Campanella) comes in with Darlene (Anjanette Comer) and Lee (Lynn Carlin) for their own party. Seeing that they've intruded, Dan invites them to stay and he brings out champagne, which Darlene thinks is divine since she loves champagne (but she really would rather have Dan to herself).
As the other party revellers leave, Dan and Darlene are caught by Kenny (Danny Goldman) getting more champagne from the supply closet. He tells them that he's supposed to lock up, but Dan tells him it's okay to leave and he'll lock up.
Kenny gets on the elevator and leaves with the others and while in the lobby, tells the security guard that everyone has left. He doesn't want anyone to know that Dan and Darlene are about to have a tryst.
While they leave, Charley (Louis Guss) the maintenance guy comes in since he has to work on the heating system on the twelfth floor. And to make sure that he manages to stay awake, he brings a fifth with him.
Back at the party, Lee tells Betty that she doesn't want Kelly and to go for it and Howard has set his sight on Ginger, since she has access to personnel records. He sweet talks her into letting him see his because he can't figure out why he's not getting any promotions, but he wants this one that he's up for.
Down on twelve, Charley drinks and after spilling some flammable liquid, sets the building on fire. Surprisingly, the fire department (and local news) are there within minutes.
After Howard reads his file, Kelly confronts him and Ginger, feeling uncomfortable decides to leave and at the door notices smoke in the vestibule by the elevators.
While the fire races upward, Thelma Overland (Pippa Scott) pulls up to Darlene's apartment building and tells the manager (Tim Herbert) that she's looking for a friend of hers who knows Darlene. He points out her parking space and says that she normally parks on the street and saves the space for her "guests" but she hasn't come home yet due to the fire.
Shocked, Thelma races off to the building.
Ginger has freaked out and in her panic, ran through the glass doors and is now rendered unconscious as the men try to figure out how to get to the thirty ninth floor.
There are three flashbacks (in order to take up time) and the first goes to Lee.
She's told her boyfriend Jim (Hank Brandt) that she's pregnant and because of this slight bedroom mistake, he tells her that he doesn't want any more kids since he has two now. Not wanting to hear this (nor the fact that he doesn't want to get married) she breaks up with him.
At the elevator shaft, the men debate who should go down and Howard goes, but before he does, his flashback is told.
He's at lunch with his daughter Cathy (Tracy Brooks Swope) and tells her that everything will change with this promotion. She tells him to stop living in a fantasy and that if he does change his thinking, maybe he and her mother can get back together. She rushes off in a crying fit.
In the lobby of the building, Capt. Packer (Norman Alder) discovers the body of Howard and realizes that there might be other people on the upper floors. He immediately calls for a helicopter.
Betty realizes that Kelly is not the man for her as he props himself up against a crack in the window sucking air into his lungs like a fish out of water. Darlene looks at Dan in disgust as he's "not doing anything" to save them.
Flashback to Dan and Thelma as it's revealed that their six year old son had died six months earlier and neither will talk about it.
When the helicopter pilot discovers the survivors, the firemen make it just in time and lead everyone to the roof, with Kelly at the front of the line.
Even though Betty is upset with Kelly, I think she was more upset that her office attire (a halter mini dress and high heels) failed to impress him, but Darlene, after having struck out with Dan, invites Kelly over to spend Christmas with her as Thelma and Dan begin their healing process.
Oh, and Lee gets a Christmas miracle as well, which is sure to please Jim's kids Cathy and Paul (Tracie Savage and Kevin Nudis).