The prosecution calls a surprise witness in Alison's trial; the girls hunt for last-minute evidence.

Aria, Emily, Hanna and Spencer feel trapped and search desperately for a way out of a bad situation.

Alison returns to Rosewood High and attempts to repair the damage she inflicted years earlier.

Testimony at Alison's trial reveals a plethora of lies; Spencer, Aria, Emily, and Caleb follow a string of clues in hope of uncovering information that will clear Hanna.

Aria watches over Ezra at the hospital, while Alison and the others set a trap for "A."

Shocking secrets come to light for Aria, Emily, Hanna and Spencer as the biggest clue to the "A" mystery is revealed.

Emily, Spencer and Hanna try to adjust to the new normal; Kenneth searches for Jessica.

The Liars try to prevent Alison from sending an innocent man to jail; Hanna seeks a normal life.

A Halloween-themed ode to viewers features interviews with cast and crew, fan questions and visits from dearly departed characters.

The girls are not feeling merry at Christmas because Spencer's murder charge looms over them. Things improve though after they see an opportunity to gather evidence to clear her name.

Aria hopes Andrew can be her tutor; Spencer helps Jonny with a new project.

Ali considers a plea deal, but it incriminates someone else, so the girls try to help her and Mike, as well as themselves. Elsewhere, Spencer unwinds while on a night out in London

Hanna's drinking gets out of control; Emily looks for information linking Alison to Noel.

The girls scramble for evidence as Alison considers a deal. Spencer has a night out on the town in London.

The girls look out for Alison's safety after she is spooked by a recent Rosewood "accident.''

Aria searches for information on a patient; Spencer borrows Ezra's spy equipment.

Hanna is pushed down a dark path after Alison moves in; Aria fails in her duties as maid of honor.

Melissa reveals her knowledge of Alison's disappearance to Spencer; Emily seeks Ezra's help.

Secrets abound for Aria, Hanna and Spencer while Emily tries to let go of Paige.

Hanna enters a beauty contest and turns to Emily for help; Aria asks Andrew to keep an eye on Mike.

Alison struggles with the death of her mother, as the Liars try to navigate through her new lie.

The Liars try to prove that Alison was involved in Mona's death; Aria worries about her future.

Mona's friend comes to town to pay her respects.

Alison attempts to regain her position as leader of the gang upon her return to Rosewood High.

Spencer and Toby are at odds while Emily and Aria struggle with situations that are out of their control.