Your complete guide to sci-fi TV season finales!

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Dec 14, 2012, 4:31 PM EST

Get ready for some drama, folks! It's season-finale time for most fall and midseason shows. People will die, lives will be forever altered, producers attempt to take the term "game-changer" to a whole new level, and some shows will get canceled or end their runs.

Here's what you can expect from 16 upcoming season finales of sci-fi and paranormal shows, by airdate. And beware ... there are spoilers ahead! (Click on the images for larger versions.)

Wednesday, May 5

Ghost Hunters (Syfy) 8 p.m.—Season-six spring finale

On tonight's episode, the TAPS team delves into the history and paranormal reports of Norwich State Hospital, located in Norwich, Conn. The hospital, also known as the Norwich State Hospital for the Insane, housed around 3,000 patients in the 1950s. Long believed to be haunted, the hospital is abandoned and has a network of underground tunnels for the ghost hunters to explore. Expect Ghost Hunters to return with new episodes later this year.

Thursday, May 13

The Vampire Dairies (The CW) 8 p.m.—Season-one finale

The hit series has already been renewed for a second season, so no reason it shouldn't go out with a bang. In the finale, "Founder's Day," as Mystic Falls prepares Founder's Day parades and fireworks, Johnathan Gilbert (David Anders) sets his plans in motion for his own explosive end to the festivities. It all has to do with the mysterious device that he's been hot to get his hands on since he arrived in town. Expect a body count (including a cast member), Damon and Alaric working together to stop Uncle John, and some heavy cliffhanger action. Also, Bonnie's relationship with the vampires will change, while more drama awaits Jeremy.

Supernatural (The CW) 9 p.m.—Season-five finale

We're guessing it's going to be a finale of apocalyptic proportions. In "Swan Song," Sam and Dean put their plan in place to stop Lucifer and the Apocalypse. But their plot to trap the devil may end up costing the life of someone we know. But it's not the end of the world as we know it: Supernatural has been picked up by The CW for a sixth season.

Friday, May 14

Smallville (The CW) 8 p.m.—Season-nine finale

Chloe puts out a call for help from members of the Justice League and the Justice Society in the battle against the Kandorians, Clark and Zod will face off in an epic battle, and a major character will die in "Salvation." But don't expect lots of closure. This wouldn't be Smallville if it didn't end with a huge cliffhanger, and the producers are promising several cliffhangers this year. Luckily, The CW has already renewed the series for a 10th season.

Tuesday, May 18

V (ABC) 10 p.m.—Season-one finale

It looks like we'll finally get an Anna/Erica face-off when Erica discovers that Anna has birthed an army of soldiers just waiting to hatch in "Red Sky." As Erica plots to take out Anna's army before it can be born, Val's V-human hybrid baby will come to term. Meanwhile, Chad learns a devastating secret. While the series is likely to end on a cliffhanger to set up a second season, there's no decision yet from ABC about whether we'll see more V.

Thursday, May 20

Fringe (Fox) 9 p.m.—Season-two finale

In the two-part season finale, "Over There," the team will indeed head over there to the alternate universe in an effort retrieve a member of the team. Remember that there's two of everything, so expect to see double when it comes to the cast. Leonard Nimoy reprises his role as William Bell. The big news—and this seems to be catching when it comes to season finales this year—is that sacrifices will be made, and a member of the team will die. Fox has renewed Fringe for a third season.

Friday, May 21

Ghost Whisperer (CBS) 8 p.m.—Season-five finale

Melinda takes on the dark forces that are terrorizing her and her son in the season finale, "The Children's Parade." When Melinda investigates what may be a poltergeist at Rockland Memorial Hospital, it leads her into the battle of her life. And she comes to discover something so scary that she just might her rethink her ghostly hobby as a social worker for the dead. No word yet from CBS regarding a sixth season.

Medium (CBS) 9 p.m.—Season-six finale

There's big drama in the season finale, "It's a Wonderful Death," when Allison's brain tumor returns, Ariel gets accepted to college and Scanlon and Lynn get married. Don't look for Allison to get off easy when it comes to her returning brain tumor. Teri Polo guest-stars as a murder victim, and Margaret Colin guests as D.A. Kelly Shuler. CBS still hasn't announced whether we'll see a seventh season of Medium.

Saturday, May 22

Legend of the Seeker (Syndicated)—Season-two series finale

Sorry, Seeker fans, but the series has been canceled. But considering how the first season ended and the syndicated nature of the show, you can likely expect Seeker to end in a way that ties up the storyline involving Darken Rahl and the Keeper, with Richard and his troupe saving the day. While we don't have a synopsis, the episode is called "Tears," which seems appropriate for the final episode of the fantasy series.

Sunday, May 23

Lost: The Final Journey (ABC) 7 p.m.—Two-hour special retrospective

Just in case you want to relive all six seasons in two hours, check out Lost: The Final Journey. According to the press release, the special takes "a look back on how it all started in 2004, what it took to produce the seminal show in Hawaii, and how it became a phenomenon in the U.S. and around the world. Past and present cast members will share their experiences working on the show and their thoughts on its coming to an end. Also examined will be the dynamic characters, themes and innovative storytelling, plus an extensive look at what has transpired during the current season." The show's series finale airs immediately after the special.

Lost (ABC) 9 p.m.—2-1/2-hour season-six series finale

Sure, like we'd spill the beans on how this one ends, even if we had a clue. Lost finally comes to a close in a special Sunday two-hour finale called, appropriately, "The End." The producers have promised that questions will be answered, but not all of them. The saddest thing of all is that when Lost goes, there will be nothing like it on TV. It's one of a kind, and if you could say that any show was more about the journey than the finale, this one would be it. But we really want to see that finale!

Monday, May 24

Chuck (NBC) 8 p.m.—Two-hour season-three finale

You get two big hours of Chuck with "Chuck vs. the Subway" (not that Subway!) and "Chuck vs. the Ring: Part 2." The original "Chuck vs. the Ring" was actually last season's finale and involved Ellie's wedding and a whole different type of ring. In the final episodes, it looks like the evil organization the Ring will be after Chuck and his crew, with Scott Bakula returning as Chuck's dad and the creator of the Intersect. Meanwhile, someone else we know will return to cause trouble for the gang. And we'll get another performance a la Jeffster.

24 (Fox) 8 p.m.—Two-hour season-eight series finale

It's been another long, long day for Jack Bauer, and it's his final one on Fox. But not to worry: The producers have promised Jack won't die, which makes sense, since a movie is in the works. In his final hour, Jack's after vengeance over the murder of Renee, he has issues with Chloe, and President Taylor's efforts for peace to all come to a head for an explosive ending. The one thing we're guessing: Jack's not going to end the day as happily as he started it. Former ER star Eriq La Salle will guest-star as the U.N. secretary-general.

The Big Bang Theory (CBS) 9:30 p.m.—Season-three finale

In the finale, "The Lunar Excitation," Howard and Raj hunt for Sheldon's perfect match online, while Penny ponders whether dating Leonard has ruined her for normal guys. The Big Bang Theory has at least one more season in its future, so there will be more Sheldon/Penny/Leonard fun to come.

Thursday, May 27

FlashForward (ABC) 8 p.m.—Season-one finale

In "Future Shock," Mark and Lloyd work together to stop another blackout, while Mark deals with the realization that he's losing Olivia. And Janis has some decisions to make regarding work versus her pregnancy. If the ratings don't improve drastically, it's looking like there's a good possibility this will be the series finale of FlashForward.

Friday, June 11

Stargate Universe (Syfy) 9 p.m.—Season-one finale

The two-part season finale, "Incursion," involves the Lucian Alliance, and we're guessing they feel they have dibs on the Destiny. When the Alliance's Commander Kiva gets on board the Destiny, several of the crew are taken hostage. Syfy has already renewed Stargate Universe for a second season, which will premiere later this year.

Friday, July 2

Merlin (Syfy) 10 p.m.—Season-two finale

When the Great Dragon is set free in the finale, "The Last Dragonlord," he's none too happy. He turns his vengeance on Camelot, and it looks like it might be the end as the castle begins to crumble under the dragon's attacks. But Merlin and Arthur discover that the only one who has the ability to defeat the dragon is a Dragonlord, and they set out to find the last one. Merlin has been renewed by the BBC for a third season, but there's no word on whether Syfy will pick it up for American audiences.

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