AMC's "The Walking Dead" may be gearing up for its most action-packed episode of the eighth season with episode 12, titled "The Key." The Saviors are rallying to attack a target that could be Hilltop, while Rick (Andrew Lincoln) and Negan (Jeffrey Dean Morgan) literally collide into each other in a car chase.

According to the episode summary of "The Key," "Hilltop's leadership faces a difficult dilemma after the arrival of unexpected visitors; Rick comes face to face with an adversary." While that little snippet does not give away much, the episode's teasers show what seems to be a tense, thrilling episode.

Rick Grimes is still reeling from the loss of his son, Carl (Chandler Riggs), who died in the mid-season premiere after sustaining a fatal walker bite. In a teaser for episode 12, he is seen kneeling over his son's grave, although there may not yet be time for him to fully grieve. After all, he and his allies are still in an all-out war against Negan and the Saviors.

In another scene, Negan's lieutenant Simon (Steven Ogg) is shown giving orders to a group of Saviors. It looks as though they are getting ready to attack but not to kill, with Simon instructing them to only scare their targets.

Perhaps Hilltop is the intended target, since another scene shows Maggie (Lauren Cohan) and Rosita (Christian Serratos) standing at Hilltop's fence, with Maggie looking out at the horizon through a pair of binoculars. A scene showing Rick shooting walkers is overlaid with a voice whispering a warning that the Saviors are on their way. Another voice answers, "We're going to fight them."

Meanwhile, it seems that Rick and Negan have found themselves about to square off once again. A scene shows Rick stalking around a dark corridor with his gun, probably looking for Negan. Negan, meanwhile, taunts Rick by telling him that he failed his son and his people as well.

"Why don't you just let me save you, Rick?" Negan asks as the teaser ends.

Another clip, meanwhile, shows Simon and defector-turned-double-agent Dwight (Austin Amelio) driving in a truck when they see Negan's car hit on its side by another car. In this clip, Rick is shown to have mown Negan's car off-course with his own, and a car chase between the two ensues.

While these clips may give viewers an idea on what to expect from the episode, a lot of questions remain. There is the possibility that Negan knows that Dwight is actually a double agent, though this is uncertain. It is also unknown what the Saviors plan to do in their attack, or if Hilltop is even their target.

Most crucial of all, of course, is the outcome of the confrontation between Rick and Negan.

"The Walking Dead" airs Sundays at 9 p.m. EDT on AMC.