Credit: Instagram

The Pretty Little Liars cast and crew are at it again: staying oh-so-late on set to finishing filming the scenes we can’t wait to see! Last night (October 17), Shay Mitchell (Emily) and Ashley Benson (Hanna) were on the job filming one of the final episodes of Season 4. Check out the pic Ash tweeted of her and her bestie on set!

“Late nights on set with @shaym,” Ash tweeted late last night, along with a snapshot of the gals looking glamorous (of course), if not tired. Shay even has her eyes closed! Maybe Ash should check to make sure her co-star hasn’t fallen asleep on her…

It looks like Ash knew this day was going to be a long one. Six hours prior, she sent out this Instagram shot of herself with some sort of under-the-eyes patches (they look like the kind that relief puffiness). “Eye patches are a must for today. Hope everyone has a great day,” Ash captioned the pic, making us think she knew she might be staying on set well into the evening.

We believe PLL is currently filming Season 4, Episode 23 (aka the episode before the season finale). Titled “Unbridled,” word on the street is that someone will get hitched in this episode! Ash and Shay didn’t look like they were sporting wedding attire...

Catch the Pretty Little Liars Season 4 Halloween special on Tuesday, October 22, 2013 at 8 p.m. ET on ABC Family, followed by the series premiere of Ravenswood!

Credit: Celebified Photo: Pretty Little Liars Halloween Special "grave New World" Preview Photos: Ezra Lurks In The Shadows While The Girls Search For Ali!