Title: Just Three Friends
Directed by: James Burrows
Written by: David Lloyd
Air Date: December 15, 1983
Previous: How Do I Love Thee, Let Me Call You Back
Next: Where There's a Will...
Guest Starring: Markie Post
"Just Three Friends" is the 11th episode of the second season of Cheers.
Diane's childhood friend Heather (Markie Post) has moved to Boston and is visiting Diane. The two of them come to the bar and, naturally, Diane introduces Heather to her boyfriend Sam. Heather's outgoing, friendly personality leads Sam to believe that Heather is coming on to him. Diane is shocked to hear this and insists on asking Heather directly, much to Sam's embarrassment. Heather denies any interest in Sam and Sam apologizes.
Diane invites both Sam and Heather over for dinner at her apartment. Sam continues to be apologetic to Diane, and in fact is proud of himself for having a woman as a platonic friend. However, Diane's insecurities start to lead her to think that Sam was right the first time and that Heather is after her man.
In the B-plot, Coach gets an attack dog to defend the bar from burglars. The idea proves ill-considered when no one can handle the wild dog, which is shut up in Sam's office.
- Ambiguous Situation: It's not really clear whether or not Sam, and later Diane, are right about Heather wanting Sam. She says "Sam I want you and I don't care who knows it," then laughs it off as a joke, but she's a little too convincing. She denies being interested in Sam at the end, but between the comments about how handsome he is, the Erotic Eating, the scene where she touches his arm and says "Ooh, muscles!"...it's ambiguous.
- Angry Guard Dog: The "beast" that Coach unwisely bought for the bar, brought into Sam's office in a cage, then left there when they realize they can't control the monster. They eventually do subdue the dog by getting it drunk—whereupon it humps Norm's leg.
- Call-Back: Heather and Diane tell a story about how they used to prank call people and pretend to be radio hosts who tell the victims that they'll win a prize if they can name three cars that start with P. After the marks name Plymouth or Pontiac or whatever, they'd say "No ma'am I'm sorry, those cars start with gas!" The Call-Back comes later in the episode when we see Cliff and Norm pulling the same prank on their moms.
- Erotic Eating: The rather excessive show that Sam and Heather put on with the spaghetti—slowly slurping noodles, moaning orgasmically—is what causes Diane to freak out and confront Heather directly.
- Just Friends: Diane insists this is all Heather wants to be, but she soon has her doubts.
- The Voice: The terrifying guard dog is never seen, only heard as barking coming from Sam's office.