Pretty Little Liars
A scene from the penultimate episode of Pretty Little Liars Season 7.Facebook/Pretty Little Liars

The penultimate episode of Pretty Little Liars Season 7, which is also the series finale, will air on Tuesday and bring viewers one step closer to finding the identity of AD or Uber A, the villain.

Watch season 7 episode 19 live at 9pm EDT on Freeform, and it can also be watched online on Freeform.go.com.

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The penultimate episode is titled Farewell, My Lovely and it is also expected to reveal the identity of the person who killed Charlotte Drake, and spoilers doing the rounds indicate it could be Mona.

One promotional photo shows the whole gang confronting someone who looks a lot like Mona, and in another photo, Mona is seen standing in front of the bell tower holding a bunch of flowers. The bell tower is from Charlotte plummeted to her death in season 6.

Meanwhile, Pretty Little Liars showrunner Marlene King revealed to ET that the mystery of Emison's baby daddy will also be revealed shortly. She also touched upon the duo's romance, pointing out that AD's antics have brought Alison and Emily even closer.

Pretty Little Liars
Lucy Hale as Aria on Pretty Little LiarsFacebook/Pretty Little Liars

 "A.D. often does things that you think are terrible to the girls, but often it backfires and it brings the girls closer together. So this is a perfect example of one of those horrible A.D. things that ultimately will bring the girls closer instead of dividing them," said King.

The summary for season 7 episode 19 reads:

Convinced they know who A.D. is, the Liars gear up for a confrontation. Spencer, Hanna, and Caleb team up to investigate and discover new information about Charlotte's death. Meanwhile, Mary Drake returns with a gift for Spencer and Alison.

Pretty Little Liars airs Tuesdays on Freeform. The final episode of the series will air on June 27 and it is titled Til Death Do Us Part. The finale will reveal who killed Charlotte. The episode is going to be high on drama.

Find below a video on our top 5 AD suspects: