'The Walking Dead': Sneak Peek of Sunday's Big Showdown Finale Featuring Rick, Glenn, Carl [Exclusive Photos]

The Governor and his minions crash the prison, but will they find their enemies or discover that their enemies have already hit the road?

Rick Grimes (Andrew Lincoln) in "The Walking Dead" episode, "Welcome to the Tombs."

Well, "Walking Dead" fans, the whole season has come down to this: "Welcome to the Tombs," the season finale, which promises to only add to the heartbreak of last week's death of bad-boy Dixon brother Merle.

Rick Grimes (Andrew Lincoln) and his group are facing an all-out war with the Governor (David Morrissey), and the photos show a pensive Rick, as well as Rick having a heart-to-heart with son Carl (Chandler Riggs), who would have to fight alongside his dad and pals when the Governor and his crew come knocking at the prison gates.

Well, not so much knocking as blowing their way into the joint. A preview of the finale show the Governor and his men blowing up the prison guard tower before barging in with weapons drawn to confront Rick and company.

Will the Woodbury citizens wreak havoc on the prison dwellers? Or will they find that Rick and the gang have already fled the prison to go find a safe haven?

It's a pretty sure-thing bet that safety is not a word that will describe anything that happens in the season ender, which has been described by various cast members as devastating, heartbreaking, and game changing.

And this is conjecture on our part, but who else didn't feel so confident about Glenn's future after he told Daryl last week that he cares more about Maggie than he does about himself? That, plus the fact that Glenn and Maggie are planning to get married … just sayin', Glenn seems to be at his most vulnerable.

Watch a preview of the finale:

"The Walking Dead" Season 3 finale airs March 31 at 9 PM on AMC.