The girls of Pretty Little Liars will investigate a clue hidden in one of Hanna's (Ashley Benson) teeth on the next episode.

ABC Family released new promotional photos for the next episode of Pretty Little Liars, titled Bite Your Tongue. The photos feature the girls examining a message on Hanna's tooth from A. The message cryptically states "Stop looking." Many photos feature the girls seemingly arguing after seeing the message.

The episode features Hanna devising a new plan to figure out the identity of the body in Ali's (Sasha Pieterse) grave. Meanwhile, Spencer pours over Ali's diary to try and look for clues about Ali's "mystery man."

Elsewhere, Aria (Lucy Hale) expresses her discomfort with the new friend Mike (Cody Allen Christian) has made while Emily's (Shay Mitchell) father is worried about her recent behavior.

Pretty Little Liars season 4B airs Tuesdays at 8 p.m. on ABC Family.

View the slideshow of promotional photos from Bite Your Tongue here: