Secrets were a big part of Pretty Little Liarsfrom the little ones that the girls didn't think twice about keeping to the really big ones that meant the difference between life and death if they shared them. And whoever knew the most secrets was the most powerful character on Pretty Little Liars, as they used those secrets to control and manipulate the others.

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Apart from the juicy secrets that kept the show going for seven seasons, there were some iconic lines about the art of keeping skeletons in the closet. Whether it was Alison coaxing a secret out of her friends that she'd later use to manipulate them or Hanna reflecting on the things people hide about their lives, Pretty Little Liars had some powerful lines about secrets.

"Friends Share Secrets. That's What Keeps Us Close."

Alison entering Spencer's barn in pilot episode of PLL

When Spencer cautioned Aria against drinking too much at their slumber party in the pilot episode, telling her she'd wind up spilling all her secrets, Alison said this quote and told everyone to drink up.

Arguably one of the most memorable quotes said during an iconic scene of Pretty Little Liars, the line is more ironic than anything, because of all the girls, Alison had the most secrets, most of which she didn't share. She also used their secrets to control them and force them to remain close to her — so in a way, secrets did keep them close just not in the fun, friendly way they'd hoped. Pretty Little Liars had many wholesome friendship moments, but this was not one of them.

"Two Can Only Keep A Secret If One Of Them Is Dead."

Alison looking down at Emily after saving her on PLL

During the first couple of seasons, the girls believed Alison was really dead. So every time they saw her, they thought she was a ghost, from Hannah's visceral dream in the hospital after A ran her over to Aria's conversation with her when she was sick at home being drugged by Meredith. In one of her appearances to Emily, Alison told her this quote when Emily asked if she knew who was torturing them.

Besides the time it was said on the show, the line is a familiar one for many fans because it's part of the Pretty Little Liars theme song, "Secret" by The Pierces. It was one of Alison's favorite lines and it reinforces the running theme of the show that no one can be trusted when it comes to keeping secrets.

"I Found A Way To Survive My Secrets, But Everyone I Care About Gets Hurt."

Troian Bellisario as Spencer Hastings on PLL

In the episode "Over My Dead Body," the girls receive individual instructions from A required to guarantee Dr. Sullivan's safety. Spencer's instructions were to keep Toby safe, which she believed to mean they had to break up. While breaking up with him, she told him she had many secrets she was keeping from him and that she didn't want him to end up getting hurt by them.

Spencer and the other girls were all forced to keep secrets because they didn't know who to trust, from the police to some of their family members. Whenever they tried to come out and tell the truth, there was always collateral damage, hence why they felt the hopelessness Spencer expressed in this quote.

"Many Families Have Secrets. Most Families, Really. And Sometimes Those Secrets Are Actual People."

Andrea Parker as Mary Drake on PLL

After Hanna was kidnapped and the others were given an ultimatum to get evidence of Charlotte's killer if they wanted her back alive, she escaped in the episode, "Bedlam." When she ran onto the road, she bumped into Mary Drake, who she realized was Jessica Dilaurentis' twin sister. Hanna commented on how strange it was that Alison had never mentioned having an aunt, and Mary told her that sometimes families kept people as secrets.

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At the time, the girls believed Mary Drake was A.D. and had been torturing them to get information on Charlotte's killer. Although this quote seemed to reference her as a family secret at the time, later revelations of the real A.D. showed there was more than one secret person in the family.

"That B*tch Can Keep A Secret. I Respect That."

Mona Vanderwall looking up at someone in Pretty Little Liars

One of the biggest plot twists on the show was the reveal that Toby was part of the A-team, like Mona. While the two of them were plotting their next move in the season 3 episode, "Misery Loves Company," Mona asked Toby if Spencer had told him that the A messages were continuing, even after she was sent to Radley. When Toby said she was still lying, Mona commended how well Spencer could keep a secret.

Mona herself was basically the queen of secret-keeping, especially considering how well she hid the fact that she was A for an entire season. The fact that Mona was impressed by Spencer keeping a secret so well may have been part of the reason why she later tried to convince Spencer to join the team too.

"Twenty Bucks For A Secret? You're So Cheap."

Alison writing in her diary on her bed in PLL

"The First Secret" was a flashback episode showing various things that had happened in the past. One of them was a scene in Alison's bedroom when Jason walked in. She asked what he and his friends were doing in his room and he demanded $20 in return for telling her, which is when she mocked him for selling a secret so cheap.

Alison thrived on secrets, even way back before her "death." The secret she discovered here was about the N.A.T Club, whose members were involved in lots of shady, secretive things happening in Rosewood.

"I'm Still Here, B*tches. And I Know Everything."

Emily, Spencer, Aria, and Hanna staring at their phones after receiving texts from A on PLL

After Alison's funeral, the girls all received text messages at once outside the church with this line, leading to one of the most memorable moments on Pretty Little Liars. That text at the end of the pilot set the tone for the entire series, as A continued to hold every secret the girls had over them.

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The text made them question whether Alison really was dead because she was the only one who knew all their secrets. It opened up the mystery of who could know all their secrets and what they hoped to gain from torturing the girls, which was the key thing to grip the audience's attention.

"Everyone's Got A Life That No One Knows About."

Hanna looking confused on Pretty Little Liars

After a confrontation between Lucas and Sean in season 1, Sean advised Hanna not to hang out with Lucas. Hanna countered with questions of her own about his friend Noel Kahn, whom she suspected to be A, and told Sean that everyone has a life that no one knows about.

This statement is true about almost every character on Pretty Little Liars. Whenever a secret was shared or exposed, it revealed something new and unexpected about the character's life. This mostly led to the liars not being able to trust most of the other characters and gave A more power over them.

"Secrets Aren't Just Secrets. They're Weapons. Things You Keep In Your Pocket Till You Need Them."

1940s version of Toby and Spencer on PLL

In season 4, episode 19, "Shadow Play," the story switched to 1940s style, including being in black and white. While talking to Spencer in an interrogation room, Toby said this line and told her he learned the principle from Ali.

The quote is a perfect summary of the entire show and how secrets gave the villains power over everyone else. Every secret and lie the girls kept and told was used as a weapon against them, first by Alison and later by A and other versions of the hooded figure.

"That's One Family Secret I Can't Keep."

Lucy Hale as Aria talking on the phone on Pretty Little Liars

In the episode "Misery Loves Company," the girls were starting to suspect that Aria's father might have hurt Alison based on some things they read from her diary. While discussing it with the girls, Aria said she didn't believe her father could have done it, but if he had that was one family secret she wasn't going to keep.

Before this, Aria had kept one major family secret about her father's affair. The secret had destroyed their relationship but she'd kept it to protect her mother. This time, faced with the choice between her father and justice for her friend, she was prepared to tell the truth.

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