Pretty Little Liars fans are on a deathwatch. Someone is about to be six-feet under, but there's one character who will defiantly not land in the Lairs' shallow grave.

Hanna Marin (Ashley Benson) is safe...for now. Caleb (Tyler Blackburn), on the other hand, will soon be MIA.

The Liars will make the biggest mistake of their lives next Tuesday. Their plan to rescue Ali (Sasha Pieterse) from Elliott's (Huw Collins) asylum of hell will result in someone's death, and the sudden twist will give Uber A the upper hand. Following the events of "The Talented Mr. Rollins" and "Hit and Run Run Run," the women will attempt to shrug off their latest mishap and deal with the return of an old foe in "Along Comes Mary" (see a preview below).

"Jenna returns to Rosewood and befriends another one of the Liars' enemies, making her the PLL's number one suspect for Uber A," Freeform teased.

As the past collides with the present once more, Ali will leave the psychiatric hospital behind. That's good news, right? Wrong. The former teacher will be put under the care of her aunt, the enigmatic and potentially deadly Mary Drake (Andrea Parker).

With Ali marginally safe (anything's safer than being around Elliott, yeah?), the rest of the Liars will have side missions of their own. It's time for Spencer (Troian Bellisario) and Hanna to put their mutual love for Caleb to work.

"Spencer enlists Hanna's help to search for Caleb as he's missing in action," Freeform announced. "Aria and Emily stumble upon a secret apartment they hope will lead them to more answers."

If Hanna isn't in the grave, who is? Where is Caleb? Is Jenna really in league with Uber A? As per usual, one Pretty Little Liars answer cost at least five questions.

Join Aria (Lucy Hale), Emily (Shay Mitchell), Spencer, and Hanna in Rosewood when Pretty Little Liars airs Tuesdays at 8 p.m. ET on Freeform.