The three single roommates Janet Wood, Chrissy Snow and Jack Tripper all platonically share Apartment 201 in a Santa Monica, California apartment building owned by Mr. and Mrs. Roper.
Jack's girlfriend wants him to be a father to her child.
Jack finds a magazine quiz about secret loves and thinks that either Janet or Terri is in love with him. He then gets them both alone in a cabin to find out who the mystery lover is.
Jack goes to an ATM machine and the machine goes haywire and spits out all of the money on Jack. He tries to get it back to the bank, but the bank is closed. Janet suggests that he hide it in the couch, which, incidentally, gets takes away by Furley who wants to put in a new couch!
Jack tries to get a scathing letter from a food critic who thinks has written a bad review about his restaurant.
Jack gets Larry to go out with Janet's visiting friend because he already had a date planned.
Jack goes out with a sex therapist and Janet thinks that she is a prostitute.
Larry enters one of Jack's recipes in a cooking contest which wins, but Jack finds out that the contest is open only to women. Jack dresses as a woman to enter a bake-off competition.
Jack's father comes to two, but Jack is mad at him because of all the heartache he had caused.
Terri goes out with a doctor who happens to be married, and the roommates plan to have the wife catch her husband and Terri together.
Jack and Larry gambles with a lot of fake money, and they lose a lot.
The trio is suspicious of a new tenant, who they think is a jewel thief and a murderer. In actuality, he is a ventriloquist practicing for his act.
Janet's aerobics job seems to be in jeopardy, and Jack tries to go out with the female boss.
To help an old school chum save her marriage, Jack agrees to talk to her husband, a very jealous, big man. However, he learns she met with someone that day and now has poison ivy and so will the man she met up with...Jack.
When they surprise a burglar robbing the restaurant after store hours, Jack and Ralph are locked in the meat freezer by the thief.
After Jack finds a stray kitten and can't keep it due to the no-pet clause, the trio leaves it at Mr. Furley's doorstep. Mr. Furley is having fun until his brother Bart sends over an apartment inspector and the cat's owner winds up at the trio's apartment.
Jack's navy buddies take him to a tattoo parlor while he's drunk.
Jack helps out an art teacher by posing nude for her class.
Jack smashes Janet's new car and fakes amnesia to save his skin. The girls realize that Jack is fooling them and decides to get even with him.
An old flower shop customer of Janet's leaves her a little something in his will and his family tries to cut her out.
While flying, Jack gets a fear of heights and a stewardess named Vicki Bradford helps him out. They even go out for the first time, against her father's wishes. Meanwhile, Philip, the guy we met in the last episode, proposes to Janet.
Jack and Vicky are really good together, despite Mr. Bradford's objections. Janet and Philip get married in the apartment, and Jack wants Vicky to marry him as well.
When Jack proposes to Vicky, Vicky turns him down cold. The reason is that she's afraid of marriage because it might fail like her father's did. They decide to live together. The trio finally moves out of their apartment and into their new lives: Terri is going to Hawaii to work with poor children, Janet and Philip move into their new place, and Jack moves into the apartment above the restaurant with Vicky. As they begin their new life together, Mr. Bradford comes in and tells him that he is the new landlord! With that, the spin-off series Three's a Crowd begins.