'Pretty Little Liars' cast on saying goodbye after hit show's 7-year run

— -- After seven years on the air, the stars of "Pretty Little Liars" are gearing up for the final episodes of the hit TV series.

Troian Bellisario, Ashley Benson, Lucy Hale, Shay Mitchell and Sasha Pieterse stopped by "Good Morning America" today to share what it's like to close this chapter ahead of the start tonight of the second half of the show's final season, the first of 10 episodes.

"It's really bizarre," said Lucy Hale. "We wrapped filming in October, but we still knew we had this week of press to promote so this is sort of our last shebang ... our last time being all together for a while. It's very weird."

The cast members reflected on the development of their characters and the show's last episodes.

"Allison -- I think she became a really strong, sweet woman, which I loved," Sasha Pieterse said of her role. "I really liked the way we ended her character, so I can't really spoil it too much but right now you guys saw that she was pregnant, right?"

"This is kind of like the love letter to the fans this season," Shay Mitchell said. "It's a wrap-up."

When asked to describe the upcoming season finale in three words, the actresses offered "game-changing," "romantic" and "shocking."

And now that fans are about to see for themselves how the show ends, Troian Bellisario said, "I'm just glad for all this secret keeping to be done because it's been stressful for us,"

With "Pretty Little Liars" show coming to a close, the cast admitted to bringing souvenirs home from the set.

"There's a poster in Ezra's old apartment, and it's now hanging in my living room," Lucy Hale said.

Troian Bellisario said, "I stole a bunch of Spencer's jeans."

The second half of "Pretty Little Liars" season 7 premieres tonight at 8 ET on Freeform.

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