"Dallas" (CBS, 1986): Soap operas had brought characters back from the dead before, but never so audaciously as this prime-time sudser did in its ninth-season finale, in which Pam Ewing ( Victoria Principal) awoke to find her presumed-dead husband, Bobby ( Patrick Duffy), alive and well in the shower. It turned out that Bobby's death and all the events that followed -- basically all of Season 9 -- were nothing but a dream Pam had.
"St. Elsewhere" (NBC, 1988): This medical drama took the "it was all a dream" gimmick to the next level, revealing in the series finale that the entire St. Eligius universe existed only in the mind of Tommy Westphall ( Chad Allen), the nonverbal, autistic son of Dr. Donald Westphall -- who, the finale also revealed, was never a doctor.
"Newhart" (CBS, 1990): This sitcom put yet another twist on the dream reveal with a surprise callback to another series. In the last scene of the series finale, Bob Hartley -- Bob Newhart's character from his 1970s sitcom -- woke up next to his wife, Emily ( Suzanne Pleshette), and recounted the crazy dream he'd just had about being an innkeeper in Vermont.
"House" (FOX, 2009): After teasing fans earlier in Season 5 with a kiss between House and Cuddy ( Hugh Laurie, Lisa Edelstein), the season's penultimate episode found the abrasive diagnostician bedding his boss after she helped him detox from Vicodin. But wait! House -- and viewers -- discovered in the following week's episode that he'd hallucinated the whole thing, and the season ended with House entering a psychiatric hospital.
"Pretty Little Liars" (ABC Family, 2012): Fans of the books may have seen it coming, but those who only know the characters from the television series didn't see when "A," the mysterious tormentor out for revenge against Hanna, Emily, Spencer and Aria ( Ashley Benson, Shay Mitchell, Troian Bellisario, Lucy Hale) was revealed to be Hanna's soon-to-be former friend Mona Vanderwall ( Janel Parrish). Her motive was apparently jealousy over Hanna's bond with the other girls, but as the final scene of the episode hints, she was taking orders from someone else.
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