Teen drama series Pretty Little Liars received plenty of praises during its run and part of the reason for that was the presence of the mysterious antagonist named "A." The modus operandi of the antagonist was to send creepy and threatening messages to the Liars, namely: Alison, Spencer, Aria, Hanna, and Emily. However, there were a couple of occasions when "A" resorted to violence too.

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The identity of "A" remained a mystery for a long time but three people who the Liars were close to, were eventually exposed as the culprits during different stages of the show. The three culprits also had a group of individuals working for them that they named the A-Team.

The following are the most chilling messages "A" ever sent.

“Heads Up, BFFs! It’s Open Season On Liars And I’m Hunting."

pretty little liars spencer aria hanna emily

"A" sent the text to Aria, Hanna, Spencer and Emily in Season One's third episode titled "To Kill A Mockingbird."The Liars were erecting a memorial in the forest next to the Kissing Rock when they heard a sound in the bushes.

A few seconds letter, they all received texts from "A" telling them that they would be dedicating their time into hunting them because of their lies. Later on when the Liars were heading back to their hangout place, they heard another noise and chased it only to find nothing. Later, a black-gloved figure was shown listening to music.

“You Didn’t Take Me Seriously So I Thought I’d Light A Fire Under Your A**.”

Burn This - Pretty Little Liars

When the Liars were at Lucas' apartment and Ashley tried to turn to the lights" everything went wrong. The air conditioner blew everything, causing one of the present bags to fall over. As Aria tried to pick the bag, the fireplace lit up and knocked her over.

The Liars looked in horror as the fire burned Aria before they managed to contain it. After that, Aria had to be taken to the ER for treatment. It was clear that "A" had gone from threats to actual violence that could lead to death. The events happened in the Season 6 episode titled "Burn This."

“Be Careful, Hanna... I Hear Prison Food Makes You Fat.”

Hanna looking at clothing in store with Spencer on Pretty Little Liars

When Hanna and Mona were shopping at a mall in the pilot episode, Hanna decided to shoplift. She stole expensive sunglasses while Mona stole a scarf. A security guard followed them shortly after but it was only to hand them a handbag they'd forgot.

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Hanna thought no one else knew about the incident until she got a text from "A" letting her know that someone was watching. "A" even warned her that prison would food would make her fat. Hanna had earlier expressed her fears of becoming overweight, vowing to do everything in her power to make sure that never happened.

“I Buried Your Mom The Same Way I Watched Her Bury You.”

Pretty Little Liars

“A” not only sent this message to Ali but also accompanied it with a video of Jessica DiLaurentis being buried in a grave at the backyard. Quite a way to pump up the creepiness.

At first, it was implied that "A" was the person that killed Jessica, but in the tenth episode of Season 6 titled "Game Over, Charles," Charlotte stated that she discovered Jessica's body right outside the DiLaurentis residence when she had escaped from police custody. It was later revealed that Jessica's twin sister was the person who killed her.

“If You Are Lying. I Shoot All Of You.”

The season four finale "'A' Is for Answers" of "Pretty Little Liars."

"A" sent this text to Hanna in the finale of Season 6. The episode saw Hanna planning to meet with "A." She also promised not to involve the police, a promise "A" reminded her to keep or else there will be consequences.

Ali and Elliott were planning to go but Emily complained that she didn't want to be alone. The Liars then agreed that it wasn't wise for either of them to be alone at that moment.

“Reminder: I Own You.”

Emily Fields on Pretty Little Liars

In Season 2's ninth episode titled "Picture This," the spooky"A" sent this message to Emily together with a photo of her lab results. The results showed that there were steroids in Emily's blood yet she didn't remember taking them.

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It turned out that "A" had actually gone to the extent of putting steroids in her pain cream so that her blood results would show traces of the growth hormones. "A" then forced her to give her phone number to one of Samara's friends just to show her who was in control.

"No Fun Chugging Lake Water, Is It? Choke On This, B*tch.”

The Liars - Pretty Little Liars

In the sixteenth episode of Season 2 titled “Let the Water Hold Me Down,” Hanna was at Spencer's house when she needed to take some drugs. She thus reached out to her bad to take out a bottle of water.

Just when she was about to take it, Emily tried to stop her since she felt the water had an unusual appearance. However, Hanna took a sip and shortly after that, she got a text from "A' mocking her for it. Pretty cruel because the lake was rumored to have dead bodies in it.

“Rat Me Out, Your Blood’s Next.”

Ian's trophy

In Season One's eighteenth episode titled "The Bad Seed," the Liars figured that Ian's Hilton Head trophy might have been used to kill Ali after Spencer discovered it had blood at the base. They thus did the most sensible thing by giving it to the police as evidence.

Detective Breyer and a couple of other police officers showed up the next day at school to let the Liars know that the blood on the trophy actually belonged to a rat. He also let them know that Ian hadn't participated in any tournament in Hilton Head. Shortly after that, "A" sent them a really creative message about ratting.

“Do Mom And Dad Know You’re Watching Murder Movies? Bet It Would Kill Them To Find Out.”

A in Pretty Little Liars

Given all that had been happening, you'd think the Liars would opt for any other genre rather than horror movies. Not at all. While unwinding one night in the late stages of Season 2, they decided to watch a movie about a serial killer.

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A few minutes into the movie, the got a text from "A" telling them that they weren't the only ones watching. The phrase "kill them to find out" was especially creepy because "A" had proved to them that they should take every text very literally. They had to press the pause button right after that.

“Cleaning Up Rosewood, One Mean Mommy At A Time. Dig We Must. Kisses.”

Aria at school in PLL

In Season 4's third episode titled "Cat's Cradle," Aria's mom Ella was considering relocating to Vienna, Austria with Zack for a year. Ella wasn't sure whether she wanted to go because she had children and responsibilities in Rosewood.

Shortly after that when Emily was arguing with Pam, Aria got the text from "A." She wasn't sure what to make of it, given her mum was considering moving away. Did "A" want to kill her mum? Or was "A" colluding with Zack to make Aria's mum leave Rosewood. Aria was justified in freaking out.

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