Frank, a former student of Mary's, returns for a lecture series, making Dick jealous, and paranoid that he is after her. When confronting Frank, however, he hints that he is gay, but Dick misreads him and is convinced that he is hinting at being an alien. Therefore, Dick begins to regularly accompany Frank to Geoffrey's Lounge, which he thinks is an alien bar. Meanwhile, Sally, Harry and Tommy receive a visit from Don, who has just inadvertently foiled a bank robbery, and decide to use their superior knowledge to rob a bank themselves. As the episode progresses, each of the Solomons dons a costume of one of the Village People (Dick as the construction worker, Harry as the indian, etc). At the end of the episode on their porch roof get-together, they are joined by Don in his police uniform to complete the tableau, and the episode ends to a Village People song.

When Playpen magazine arrives at Pendleton, looking for students to pose nude, Sally decides to take part. While Dick encourages this, Don is furious. Dick is horrified when he discovers that Mary posed nude for an art shoot twenty years ago, and tracks down the photographer. Harry decides to test if clothes are "all a big scam" by becoming a nudist. Tommy has his eyes on his new lab partner, Alissa Strudwick.

The Solomons reflect on their sinful ways in an episode that illustrates their misdeeds in clips from past episodes.

When Tommy catches a bug, the crew gets its first taste of human illness.

Dick is introduced to the concept of birthdays--and it dawns on him that he's getting old.

Dick's one lonely guy when Dr. Albright goes on vacation. Sally and Harry are lured by skin-care products that promise eternal youth.

Dick decides to "rehabilitate" one of Officer Don's prisoners, so he pays his fine and takes him home; Mary decides to give away the dog Dick gave her.

Dick takes Mary up to his penthouse and wines and dines her, but she tells him that she doesn't believe in true love anymore, no matter how hard he might try to persuade her otherwise. Meanwhile, Sally isn't happy being second fiddle to Don's wife so she asks him to break up with her. Don, however, wants to run for president and so refuses, so Sally breaks up with him; while at NBC, Tommy's huge ego and demand for a high pay on Saturday Night Live leads Harry to fire him.

Mary's wealthy sister Renata Albright has donated a large sum of money to have an extension built onto Pendelton University, but Mary knows that it is in fact a spiteful gesture designed to quite literally block the sunlight into her office. To retaliate, Dick schemes with Mary that he will woo Renata, win her, and then break her heart. Meanwhile, Sally and Harry are given ten thousand dollars by Renata to convert their house into a teen center.

The Solomons visit a parallel universe, in which they are living in New York City, where Dick is a highly regarded attorney, Sally writes a sex column and Harry is President of NBC, while Tommy is a star on Saturday Night Live. Despite this, Dick is unhappy because he cannot find Mary; however, upon entering a basement bar he discovers her, a failed actress-turned torch singer who has renamed herself Kiki Lyle. Meanwhile, Sally discovers that Don is the Mayor of New York, and that she isn't his girlfriend, but his mistress.

Mary's mother Martha arrives in town and Dick decides to tell her what Mary really thinks of her - that she ruined her childhood. Angry, Martha tries to attack Dick and falls over, ending up in hospital. When Dick goes to visit, however, Martha tells him her side of the story, and a deeply moved Dick takes her side and promises to tend to her during her recovery. Meanwhile, Harry and Sally get a nasty surprise when throwing junk in the time space portal - a new alien.

Dick accompanies Mary and Nina to a book-signing for a self-help book entitled 'A Road Map to Happiness', and despite first thinking it stupid, Dick opens the book and is immediately converted. He then concludes that his relationship with Mary stands in the way of his happiness, and attempts to break up with her. At college, Tommy is attempting to get into a fraternity but is doubtful that he'll pass the entry rituals, so he enlists Sally's help, but she just ends up making it harder. Meanwhile, Mrs. Dubcek gives Harry the job of painting the kitchen ceiling, and he is determined to create a work of art.

Dick and Mary decide to go on a double date with Sally and Don, but things start to become uncomfortable when Dick and Sally begin talking incessantly about how good their other half is in bed. The next day Dick and Sally come to realize that neither Mary or Don said anything about how good they are, and immediately worry that they aren't. Meanwhile, in a food store, Mary and Don run into each other and, consumed by what they'd heard about each other in bed, share a kiss. Elsewhere, Harry and Tommy follow in the footsteps of Jack Kerouac and take to the open road.

Dick and Mary visit a psychic together, who claims that the pair are from two different worlds and predicts that Dick will one day up and leave Mary. Horrified at this news, Dick decides to find a replacement boyfriend for her, settling on a man called Gary; who thinks he's actually being offered Dick's position of physics professor. Meanwhile, Sally and Harry decide that if the psychic really knows that they are aliens, then they must kill her, but in a way that isn't possible for her to predict.

While Sally does a slow burn at being the often-overruled second in command, Dick lights up his life by taking up smoking.

Dick discovers the emotion of jealousy when Dr. Albright's old boyfriend returns to visit on a promotional tour of the novel he dedicated to her. Harry adopts a stray dog.

A snowstorm -- the Solomons' first -- spoils Dr. Albright's trip to Chicago, leaving her stranded in a truck stop with Dick.

The Solomons learn about the give and take necessary to human friendships when they turn their anthropological gaze to the next-door neighbors.

Flummoxed by feminism, Dick dons a dress to infiltrate Dr. Albright's women-only study group. Harry and Sally get jobs at a pancake restaurant.

Dick decides that the Solomons don't “fit in” on Earth, so he shops for an ethnic group to join. Meanwhile, Sally wants to fit in with Tommy's handsome teacher.

The Solomons' faith in human nature is shaken when they fall victim to crime (“This planet is in a bad neighborhood,” sighs Sally). Meanwhile, Dick makes Tommy join the school basketball team.

Dr. Albright finally agrees to date Dick and Harry receives an ominous message from the home planet.

Romantic woes between Sally and Randell don't deter Harry from signing up with a dating service. August tests Tommy's loyalty.

A jealous Dick decides to show Mary how funny he is after she asks another professor to emcee a college fund-raiser she's organizing. Meanwhile, Harry loses his beloved coat, and Sally builds a shelf to hold her shoes.

A Frenchman asks an unwitting Sally to marry him so that he can remain in the country. Tommy discovers he has a talent for flower arranging and styling. Dick is inspired to discuss marriage with Albright.