With the midesason finale of The Walking Dead Season 6, Start to Finish, airing next week, AMC has released a new preview and a clip for the final episode of 2015. If you didn't catch last night's episode of The Walking Dead, Head's Up, there will be a massive SPOILER in the clip, so be sure to watch at your own risk. If that wasn't enough, we also have new photos from both Head's Up and Start to Finish. This is your last chance to avoid any spoilers, so stop reading now if you didn't watch last night's episode.

At the end of Head's Up, a large tower just outside the Alexandria walls, came tumbling down, breaching the wall and giving the zombies a way in to this once-peaceful town. The trailer for Start to Finish reveals numerous zombies flooding into Alexandria, as Rick (Andrew Lincoln) tries to lead the Alexandrians to safety. With the walls breached, will Rick and the rest of his crew be forced to leave their new home? We'll find out in just a few short days.

Head's Up also finally revealed the fate of Glenn (Steven Yeun), after he fell into a zombie herd when Nicholas (Michael Traynor) killed himself in the third episode this season, Thank You. While many fans believed that he was being eaten alive by these zombies, it turned out to be Nicholas who was being eaten on top of him, as Glenn barely managed to get out alive. After Glenn made it out, we also saw the return of another missing character, Enid (Katelyn Nacon), who hadn't been seen since the second episode of The Walking Dead Season 6, JSS.

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The clip features both Glenn and Enid, who have made their way back to Alexandria, only to find that the wall has been breached. While Glenn comes up with a plan to get around the zombies, it's clear that Enid doesn't want to go back. In Head's Up, we also saw another conflict that Enid is indirectly involved in, where Enid's boyfriend Ron (Austin Abrams) is seen sneaking into the pantry to steal some bullets, and at the end of the episode, he's seen following Carl (Chandler Riggs), seemingly with the intent to kill him.

AMC hasn't announced when The Walking Dead will return after its midseason hiaturs, but the show was renewed for Season 7. We also reported that the long-awaited villain Negan has finally been cast, with Jeffrey Dean Morgan set to guest star in the The Walking Dead Season 6 finale, before becoming a series regular in The Walking Dead Season 7. Check out the new videos from the midseason finale, along with photos from both Head's Up and Start to Finish and the special message from Steven Yeun, which aired during last night's episode of Into the Badlands.

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