Mary Ann Singleton makes her vacation in San Francisco permanent, and after a brief stay with her friend Connie, she is welcomed by her new ""family"" at 28 Barbary Lane. It's not long before Mary Ann finds herself seduced by her new boss's son, Beachamp. Michael ""Mouse"" Tolliver returns to 28 Barbary Lane to live with his friend Mona Ramsey.
The Characters continue their emotional, social and sexual meandering: Beauchamp and Mary Ann; Brian and Connie and then Hillary; DeDe and the grocery boy; Michael and Chuck and then Jon Fielding. Edgar and Anna trade a joint for a kite and Mona trades her job for her pride. Mrs Madrigal helps Edgar in a time of need. Mary Ann contemplates leaving San Francisco.
Mary Ann joins Vincent on the crisis switchboard; is confronted by DeDe and encounters the strange Norman Neal Williams. Anna takes Mona to "Beach Blanket Babylon". Edgar tells Anna he is dying. Mona's ex lover, D'orothea returns to town and wants to rekindle an old romance. DeDe escapes to a fat farm. Michael "Mouse" wins the Mr Endup Contest and ends up losing Jon.
We begin this installment on Feb 14, 1977 -- and what a strange Valentine's Day it is! Mary Ann surprises Mouse with two tickets for a Carnival Cruise bound for Mexico. Mona gets a phone call from her mother, who demands that Mona move out of Mrs. Madrigal's apartment. DeDe tells Beachamp that her unborn children aren't his. And Brian, who's moved into the upstairs apartment formerly occupied by Norman, spies on a female neighbor across the street who's spying on him. The day that Mary Ann and Mouse head off on their trip, Mona, dissatisfied with her life, leaves Barbary Lane, searching for something meaningful. She winds up smoking an angeldust joint, and buying a ticket to Reno, Nevada. While waiting for the bus, she meets motherly, but foul-mouthed, Mother Mucca, who eventually invites Mona to accompany her back to Winnemucca to be the receptionist at The Blue Moon Lodge -- the whorehouse she owns. Frannie becomes obsessed about her appearance and contemplates getting a facelift.
Mona (who introduced herself as Judy to Mother Mucca) gets the hang of things at The Blue Moon Lodge. Mrs. Madrigal, lonely with her ""family"" deserting her, worries about Mona and in a moment of exasperation, reveals to Brian that she's actually Mona's father. Mary Ann shares a romantic evening with Burke, while Mouse tries to find a crew member to seduce. DeDe leaves Beachamp and moves back in with Frannie. Mother Mucca convinces Mona to don a nun's habit and entertain (er... discipline) a gentleman client. Brian and his spying neighbor begin sharing long-distance sexual encounters -- which are being watched by the high-and-mighty queens down the street. Mona discovers a cookbook with ""Mona Ramsey"" written inside, which she learns is also Mother Mucca's name. Confused, Mona calls Mrs. Madrigal, who reveals the truth about their unique relationship.
Beauchamp arranges to have a young thug named Douchebag whack DeDe in the stomach to ensure she has a miscarriage. Mona takes Mother Mucca back to Barbary Lane to meet her estranged child. Meanwhile, Michael is initially jealous that Mary Ann and Burke have hooked up, until a chance encounter reunites him with Jon. DeDe and her new friend D'Orthea begin to bond, as do Mrs. Madrigal and Brian. Frannie joins the Pinus club, a club for wealthy 60+ women.
Mary Ann and Michael return from their trip, so Mrs. Madrigal takes the opportunity to gather all of her ""children"" to reveal that she used to be Andy Ramsey, and she's Mona's father. Mary Ann tries to discover why Burke vomits whenever he sees roses. Michael and Jon are officially back together.... just in time for Michael to be strickened with a rare paralysis. Mona later arrives with a letter from Michael's mother, in which she rants about homosexuals, so he dictates a response outting himself. Frannie goes away to an exclusive club for older women, where she's attended to by a young, naked man. Mary Ann and Beachamp have a heated confrontation which ends with her quitting. Douchebag is all set to rough-up DeDe, and awaits the word from Beachamp... but the call never comes since Beachamp ends up in a fatal car accident.
DeDe has an underwhelming reaction to the news of Beauchamp's death. Mary Ann discovers that Beauchamp didn't inform anyone that she'd quit, and she still has a job ""after the dust settles."" She uses her newfound free time continuing to play Nancy Drew, trying to unlock Burke's amnesia, and discovers that he may have been pursuing a story about a cult. Frannie gets initiated into the Pinus club. Mona and Brian spend an evening together and develop a friendship â€“ until she accidentally catches him masturbating while watching a neighbor with binoculars. Michael slowly regains use of his body, and Jon makes plans to move in and nurse him back to health. Mona receives a call from her mother, Betty, who declares that she ""could be in serious danger,"" so Mona agrees to see her.
D'Orthea accompanies DeDe to the hospital when she goes into labor and their true feelings for each other finally emerge. Betty tells Mona that she knows Mrs. Madrigal is her father, so Mona arranges a meeting between the estranged couple. Mary Ann and Burke finally figure out why he had amnesia, and it does relate to a cult â€“ a cannibalistic religious cult! Jon brings Mouse back to his newly redecorated apartment in Barbary Lane, and the two seem to be destined to spend the rest of their lives togetherâ€¦. DeDe and D'Orthea leave with the twins, headed for Jonestown.
Mary Ann and DeDe's Alaskan trip turns out to be a wild goose chase, so they return home. Luke, too, has returned to California, and it's up to Prue to help reunite DeDe with her children. Mrs. Madrigal and her family hold Bambi hostage until Mary Ann can return, during which time, Mother Mucka figures out who Bambi actually is. After Mother Mucca makes her discovery, she returns home to Winnemucca. Jon resurfaces, looking to rekindle his relationship with Michael, though it's hinted at that he's becoming ill. D'Orthea returns shortly after DeDe was reunited with the twins. Mary Ann and Brian get married shortly after Mrs. Madrigal receives news that Mother Mucca has passed away.