We knew Season 4 of Pretty Little Liars was going to be "heartbreaking" for Toby as he and Spencer dive into his troubled past, but we didn't imagine it to be so tragic. 

At the end of the Season 4 premiere ("A Is For A-l-i-v-e"), Toby made a deal with "A": He'd give the hooded enigma his/her mobile lair back in exchange for info about his mom's death. However, the Liars aren't going to be happy once they find out Toby gave "A" the RV — especially his girlfriend Spencer. After all, it was the only piece of valuable information they had against "A". 

In an exclusive Facebook clip from Season 4, Episode 2 ("Turn of the Shoe"), Toby tells Spencer what her did. "I moved the RV. 'A' asked for it in exchange for something I wanted," he explains. Naturally, she's upset. 

"What did you want? Did you think that making more deals with the devil was going to protect us?" says Spencer.

So what did "A" give Toby in exchange for the lair? "It's a transcript written by my mother's doctor at Radley. It was written on the night." 

"What night," Spencer asks. "The night my mother killed herself," Toby responds.

Whoa. We knew something was up with Marion Cavanaugh in that flashback scene, but was she seriously that depressed? Perhaps Spencer will bring Toby to meet Eddie Lamb (Reggie Austin) at Radley? It sounded like he knew all about Marion when Spencer was admitted after her breakdown in Season 3.

Whatever happens, make sure you have your tissues ready for this episode, Spoby fans. 

Are you as excited as we are to get to know more about Toby's past this season? Sound off in the comments!

Pretty Little Liars Season 4 premieres on Tuesday, June 18, 2013 at 8 p.m. ET/PT on ABC Family.