Spencer finds evidence that ties her father to Mrs. DiLaurentis' death and Mona prepares to strike against Ali in Pretty Little Liars "Thrown From The Ride."

Aria Can't Stop Thinking About Shana

Hanna (Ashley Benson) shows up at school with black streaks in her hair – a change from her usual blond ‘do. At the Rosewood High book fair, Hanna and Aria (Lucy Hale) pick out Shana’s (Aeriél Miranda) old copy of The Scarlet Letter and find a highlighted passage that Aria thinks is about them, Ali and Jenna (Tammin Sursok). As Hanna throws it back onto the pile, Mona (Janel Parrish) shows up with her new minions and tells them that they should give the book to Ali (Sasha Pieterse). Shana won’t need it, she says, didn’t Shana go back to Georgia?

Ali is cleaning out her closet – she’s not the same girl she was when she left, and she wants a fresh start, which means a new wardrobe. Besides, she needs to make some room for new school supplies. Her father (Jim Abele) tries to convince her that they should move a few towns away, where he moved to after he split from her mother, but Ali refuses – she can’t leave her friends.

At Rosewood High, Lucas (Brendan Robinson) and Mona meet, and Lucas tries to convince Mona to call off her evil plan to get rid of Ali. He believes Ali’s story about being kidnaped and he just wants to let her be. Mona tells him that Ali lied and she can prove it.

At lunch, the girls commiserate over being stared at and constantly questioned about Ali’s return. Aria is convinced Mona knows about Shana and will try to get revenge. And Aria is disappointed when she receives a mass e-mail from Ezra, thanking the students and faculty of Rosewood High for their support and well wishes. While reading the e-mail, Aria gets a chat request from ‘THEATREGIRL.’ “If it was me, I could never forget. It would haunt me for the rest of my life,” the user writes. But, when Aria asks who it is, ‘Theatregirl’ responds that it’s Becca from class and she’s actually talking about Alison. Freaked out, Aria searches for information on Shana and finds video footage from her memorial service.

Paige Warns Emily About Standing With Ali

Emily continues to help Sydney (Chloe Bridges) with her swimming, focusing on swimming while ignoring Ali’s calls and texts. When she runs into Paige (Lindsey Shaw) in the locker room, Emily decides to invite her ex to join them. After their work out, the three girls are grabbing pizza, having fun, when Paige makes eye contact with Mona and shuts down.

Later that night, Mona approaches Paige and asks her to join her team again. Paige doesn’t want to be involved, but Mona’s not going to let her off the hook. “You don’t get to be a social Switzerland here. If you’re not with me, you’re against me,” Mona threatens Paige.

After that, Paige goes straight to Emily to warn her to steer clear from Ali if she returns to Rosewood High. People that Ali hurt are planning something, though she doesn’t say what, and Paige makes it clear that she won’t be able to help protect Emily from becoming collateral damage if she sticks close to Ali.

Ali needs to undergo a medical exam as part of Detective Holbrook’s investigation. She begs her father not to make her go. Ali doesn’t want to go to her medical exam alone, so she calls Hanna and asks her to take her. During the appointment, the doctor notices a huge scar on her thigh and asks her how she was hurt. She lies and tells him that she cut herself when she jumped out of the car to escape from her fictional captors. The doctor can see that the wound doesn’t match up to her story, but Ali freaks out at him and he relents. After the exam, Ali takes out an electronic tape recorder and gives it to Hanna. She needs Hanna to make copies for Aria, Emily and Spencer so that they can memorize it for when someone starts asking questions again.

After the doctor’s exam, Hanna returns to her hold ways, shoplifting a cute skirt and top while shopping for her new look. In the dressing room, Hanna gets a call from Spencer, who tells her that they shouldn’t memorize what Ali told the doctor. She doesn’t want to be so wrapped up in Ali’s lies, but Hanna doesn’t feel like taking the brunt of Spencer’s anger. If she has a problem, she can tell Alison herself.

Emily finally goes to visit Ali and tells her that starting over in a new town might not be such a bad idea, but Ali tells her that she’s only there because of her and that if they stick together, they’ll be fine. Emily promises Ali that she’ll memorize the recording, but this is the last time she’s going to lie for her.

Did Spencer's Dad Kill Mrs. D?

Spencer makes plans with her study buddy Andrew (Brandon Jones), who approaches her to make sure that she isn’t taking pills again. She recruits him to help her with some gardening out back that has been stressing out her mother. She thinks that her mom is obsessing over her flowers to avoid thinking about the dead Mrs. D (Andrea Parker) found buried in their backyard. While taking a break in the shed, Andrew and Spencer stumble upon a dead rat, poisoned by a bucket of rat poisoning. Andrew notes that the rat poison was bought a few weeks ago – around the time Ali’s mother died.

Meanwhile, Spencer tries to get her mother (Lesley Fera) on her side to try to find out what Melissa (Torrey DeVitto) and her father (Nolan North) are hiding from them, but Veronica just wants to let it go. Later, Veronica finally opens up to Spencer. A few days after Ali went missing, Mrs. D confronted the Hastings and told them that she thought that Spencer had hurt Ali and she was going to go to the police. Mr. Hastings threatened to tell her husband about their affair, so she kept quiet. But, with Ali alive and the DiLaurentises getting a divorce, nothing was keeping Mrs. D from going to the police and telling them that Spencer killed whoever was in Ali’s grave. Veronica has a sick feeling that Mr. Hastings may have killed Mrs. D to keep that from happening. When the toxicology report for Mrs. D comes back, and it turns out that someone messed with her blood pressure pills. Mrs. D had low blood pressure, but she had Losartan in her system, which is used to treat high blood pressure. The Losartan essentially stopped her heart. It wasn’t rat poison, and when she tells Spencer, the two bond over wondering if their parents are capable of murder. Spencer’s relief is short lived when she finds Losartan in her family’s medicine cabinet later that night.

Aria, meanwhile, can’t stop thinking about Shana’s family and watching Shana’s memorial video. Unable to sleep, she goes to see Ezra (Ian Harding), who tells her that she needs to forgive herself. He tells Aria that she has to find a way, not to get Shana’s family to forgive her, but to become okay with the idea that she might never get the forgiveness. Instead, she’s really going to have to come to terms with it herself, just like he did after Aria found out about his book. To help get her mind off Shana, Ezra gets them takeout and board games. Aria asks Ezra if she can spend the night at his place – on the couch – so she doesn’t have to go home to an empty house, but she gets nervous and leaves after he hands her the t-shirt she liked to sleep in.

Aria decides to spend the night at Spencer’s instead, and Spencer tells her that she suspects her father killed Mrs. D and that her mother thinks so too. Just then, Mr. Hastings walks in and announces that Veronica had a bit of a meltdown when the police came to visit earlier, so he dropped her off at a spa for a few days and she is not to be contacted.

Pretty Little Liars airs Tuesdays at 8 p.m. on ABC.

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