Mona's return to Pretty Little Liars' Rosewood will be fraught with troubles, not least of which will be a visit from Lesli Stone's mysterious sis.

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From faking her death to landing in A's Dollhouse, Mona (Janel Parrish) has had a difficult year, all of which will need to be explained to the police in episode 5, "She's No Angel." Rosewood PD won't be the only one looking for answers, however, and yet another Stone will wonder into town as the A mystery builds to a crescendo.

"Mona returns to Rosewood in a very fragile state as she must answer to the police for faking her death," ABC Family teased. "Matters only get worse when she is confronted by Lesli's (Elizabeth McLaughlin) sister about Lesli's inadvertent involvement in Mona's plot."

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The last time viewers saw Lesli, she was implicating Alison (Sasha Pieterse) in the alleged death of her pal Mona. While the redhead may or may not return in episode 5, it seems Mona will certainly have her hands full. Luckily, the former 'A' will have at least one Liar on her side.

"Hanna (Ashley Benson) is determined to help Mona out, not only to reassure her she is safe from Alison but also to try and repair Mona's friendship with Lesli," ABC Family announced.

Find out more when Pretty Little Liars airs Tuesdays at 8 p.m. ET on ABC Family. Click the video below to get a look at the series' next episode, "Songs of Experience."