01of 10The Office’s Season 2 FinalenbcThe Office’s “Casino Night” episode released a full two seasons' worth of tension in just 28 minutes. The non-stop flirting between smitten office drone Jim Halpert (John Krasinski) and the engaged-to-another object of his affection, Pam Beesley (Jenna Fischer) came to a head with Pam’s wedding to Roy just around the corner — and Jim considering a transfer to a different Dunder Mifflin location to spare himself the heartbreak.As Pam packs up in the empty office at the end of Dunder Mifflin’s Casino Night, Jim takes the opportunity to confess his crush to her. She protests that he “misinterpreted” her friendliness and she can’t be with him — but the kiss they share sends sparks into space, and leaves fans on the edge of their seats until next season.

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The Office’s Season 2 Finale

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The Office Jim and Pam kiss

The Office’s “Casino Night” episode released a full two seasons' worth of tension in just 28 minutes. The non-stop flirting between smitten office drone Jim Halpert (John Krasinski) and the engaged-to-another object of his affection, Pam Beesley (Jenna Fischer) came to a head with Pam’s wedding to Roy just around the corner — and Jim considering a transfer to a different Dunder Mifflin location to spare himself the heartbreak.

As Pam packs up in the empty office at the end of Dunder Mifflin’s Casino Night, Jim takes the opportunity to confess his crush to her. She protests that he “misinterpreted” her friendliness and she can’t be with him — but the kiss they share sends sparks into space, and leaves fans on the edge of their seats until next season.

02of 10Lost’s Season 3 FinaleMario Perez/Disney General Entertainment Content via GettyThe third season finale ofLostanswered the long-held question of whether the crash victims ever leave the island they’re stranded on. At this point, fans had come to anticipate flashbacks throughout each episode, but in the finale, fans saw what appeared to be a flashforwardinstead, depicting Jack Shephard (Matthew Fox) and Kate Austen (Evangeline Lilly) in the same off-island scene.This reveal not only twisted the plot – for viewers, it threw the fates of the characters into question and gave light to possible life beyond the island.

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Lost’s Season 3 Finale

Mario Perez/Disney General Entertainment Content via Getty

LOST - “Through the Looking Glass” - Jack and the castaways begin their efforts to make contact with Naomi’s rescue ship, on the season finale of “Lost,” WEDNESDAY, MAY 23 (9:00-11:00 p.m., ET), on the Disney General Entertainment Content via Getty Images Television Network.

The third season finale ofLostanswered the long-held question of whether the crash victims ever leave the island they’re stranded on. At this point, fans had come to anticipate flashbacks throughout each episode, but in the finale, fans saw what appeared to be a flashforwardinstead, depicting Jack Shephard (Matthew Fox) and Kate Austen (Evangeline Lilly) in the same off-island scene.

This reveal not only twisted the plot – for viewers, it threw the fates of the characters into question and gave light to possible life beyond the island.

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The Good Place’s Season 1 Finale

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THE GOOD PLACE – “Michael’s Gambit” Episode 113 – Pictured: Kristen Bell as Eleanor Shellstrop – (Photo by: Vivian Zink/NBCU Photo Bank/NBCUniversal via Getty Images via Getty Images)

The demon who orchestrated that particular mind-bending torture, Michael (Ted Danson), decides to reset the whole scheme once he gets found out. However, just before her memory is erased and reset, Eleanor gives a note to Janet, the afterlife’s not-a-human assistant. In the rebooted afterlife, Janet delivers the note, which tells Eleanor to find her “good place” soulmate, Chidi.

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Dallas' Season 3 Finale

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Actor Larry Hagman, as J.R. Ewing, lying on floor wincing in pain after being shot in scene fr. TV series Dallas. (Photo by Arthur Schatz/Getty Images)

The question even made its way to a July 1980 cover of PEOPLE magazine, where the feature inside included a survey of Texan celebrities (including Dan Rather and George Bush) taking a guess atwhodunit. After eight months of speculation, the season 4 premiere revealed it was (okay, we won’t spoil it for you after 42 years, but you can click to find out).

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The Equalizer Season 2 Finale

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“Boom.” – In the aftermath of her abduction, the walls between McCall’s family and vigilante life continue to crumble as those closest to her must come together for the first time to save her, on the third season premiere of THE EQUALIZER, Sunday, Oct. 2 (8:30-9:30 PM, ET/PT) on the CBS Television Network, and available to stream live and on demand on Paramount+. Pictured: Queen Latifah as Robyn McCall.

Their strained relationship looked to be turning a corner inThe Equalizer’s season 2 finale, when Delilah turned to her mother for help with a friend’s complicated situation. But just as they seemed to be reaching an understanding, a mysterious kidnapping in the final scene puts far more than familial bonds in jeopardy.

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The Simpsons' Season 6 Finale

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Simpsons - Season 6 Finale, “Who Shot Mr. Burns? - Part I”

The hype fromDallas' season finale had enough of a cultural impact to influence other season-enders as well, includingThe Simpsons. The FOX cartoon split their bullet-based mystery into two episodes: “Who Shot Mr. Burns? - Part One” closed season 6, and “Who Shot Mr. Burns? - Part Two” opened season 7.

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Grey’s Anatomy’s Season 5 Finale

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Grey’s Anatomy - Season 5 Finale, “Now or Never”

In the final moments of the episode, Izzie’s heart stops after a successful surgery, prompting Chief of Surgery Richard Webber (James Pickens Jr.) to violate her DNR. Meanwhile, a car accident victim rendered unrecognizable is revealed to be George O’Malley. Doctors defibrillate Izzie’s heart in one room and operate on George in another. Meanwhile, the two meet in a vision, leaving viewers questioning if either original intern will live to see another season.

08of 10Breaking Bad’s Season 2 FinaleAMCSeason 2 ofBreaking Badsees Walter White (Bryan Cranston) devolve further into his merciless drug lord alter ego, Heisenberg. There is no character Walt won’t cross, lie to or kill in order to dominate the meth cartels, and that includes deciding to let colleague Jesse Pinkman’s (Aaron Paul) girlfriend die in the season’s penultimate episode.Walter almost undoes all his work when he accidentally refers to his burner phone in conversation with his wife, prompting her to investigate – and eventually leave him when she realizes she doesn’t want to know the truth. And fans know the stakes are high considering her DEA agent brother-in-law is on an ongoing mission to bust Albuquerque’s methamphetamine ring.

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Breaking Bad’s Season 2 Finale

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Breaking Bad, Bryan Cranston | This chemistry teacher definitely gets an A for knowing his subject matter. — AW

Season 2 ofBreaking Badsees Walter White (Bryan Cranston) devolve further into his merciless drug lord alter ego, Heisenberg. There is no character Walt won’t cross, lie to or kill in order to dominate the meth cartels, and that includes deciding to let colleague Jesse Pinkman’s (Aaron Paul) girlfriend die in the season’s penultimate episode.

Walter almost undoes all his work when he accidentally refers to his burner phone in conversation with his wife, prompting her to investigate – and eventually leave him when she realizes she doesn’t want to know the truth. And fans know the stakes are high considering her DEA agent brother-in-law is on an ongoing mission to bust Albuquerque’s methamphetamine ring.

09of 10The Vampire Diaries' Season 3 FinaleBlake Tyers/The CWFrom the beginning ofThe Vampire Diaries, fans waited to see whether Elena Gilbert (Nina Dobrev) would eventually turn into a vampire, despite her best attempts to remain human.The season 3 finale opens with Elena in the hospital, having sustained a “concussion” after collapsing in the previous episode; it ends with her back in the hospital, having presumed to be drowned after a car accident.Fans and characters alive briefly believe Elena to be dead until Dr. Meredith Fell (Torrey DeVitto) explains that vampire blood was used to ameliorate her previous head injury, meaning the healing substance was in Elena’s system when she drowned. The season ends just as Elena’s vampiric life begins. A new era ofThe Vampire Diariesawaited viewers in season 4.

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The Vampire Diaries' Season 3 Finale

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THE VAMPIRE DIARIES “The Departed” Pictured: Nina Dobrev as Elena. Blake Tyers/The CW © 2012 The CW Network, LLC. All rights reserved.

From the beginning ofThe Vampire Diaries, fans waited to see whether Elena Gilbert (Nina Dobrev) would eventually turn into a vampire, despite her best attempts to remain human.

The season 3 finale opens with Elena in the hospital, having sustained a “concussion” after collapsing in the previous episode; it ends with her back in the hospital, having presumed to be drowned after a car accident.

Fans and characters alive briefly believe Elena to be dead until Dr. Meredith Fell (Torrey DeVitto) explains that vampire blood was used to ameliorate her previous head injury, meaning the healing substance was in Elena’s system when she drowned. The season ends just as Elena’s vampiric life begins. A new era ofThe Vampire Diariesawaited viewers in season 4.

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Gossip Girl’s Season 3 Finale

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Leighton Meester on the set of “Gossip Girl” outside Milly Madison Avenue on September 16, 2011 in New York City

After drowning his sorrows at a bar, Chuck is mugged on the streets of Europe. He offers money but the thieves take something far more valuable to him: an engagement ring obviously intended for Blair. When he tries to fight back, one of the assailants fires a bullet. The scene leaves Chuck shot and lying on the ground (and fans' jaws on the floor).

source: people.com