In a small moment sandwiched between a lot of daddy drama, Spencer (Troian Bellisario) spotted a mysterious figure in black on a motorcycle. The figure drove towards her, looked like (s)he was going to stop, and then sped away.

Spencer immediately thought of Toby (Keegan Allen), which makes sense — Toby is the Rosewood resident we most associate with motorcycles, and he has plenty of reasons to drive away without saying anything after seeing Spencer. However, anyone dressed all in black, covering their face, reminds us of "A."

So, who was the mysterious driver? We've collected all the clues we can find about his/her identity.

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Toby is back: A major clue that the driver was Toby is that we know he's back in Rosewood as of next week (Season 2, Episode 23: “Eye of the Beholder”). This sneak peek shows that he's definitely still sand-offish towards Spencer, so it makes sense that he might drive away after spotting her instead of letting her know he's back in town.

Marlene Weighs In: Another big hint that it's Toby comes from showrunner Marlene King. When a fan asked her on Twitter, "Was that Toby on the motorcycle?" Marlene cryptically replied, "Spencer thinks it was. I do to." Marlene would know! Of course, she's known to be misleading, so this could be a misdirect to keep the mystery alive.

As a fun side-note: The episode's co-writer Bryan Holden tweeted about there being a "cool rider" in the episode. The other writer, Charlie Craig responded to a compliment from other crew members with. "Thanks, everybody. I miss you. And my bike." We wonder if Charlie is actually the person who rode the bike — after all, even if it turns out to be Toby on the show, they probably didn't bring Keegan in to film one scene where you didn't see who he was.

Nothing is as it seems on this show, so we wouldn't be shocked if the rider turned out to be someone far more sinister than Toby. What do you think?

Be sure to tune in for the next episode of Pretty Little Liars tonight on Monday, March 5 at 8 p.m. ET/PT on ABC Family.

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