Pretty Little Liars executive producer Marlene King has been using a hashtag for the Season 4 finale: “#AliTellsAll.” This implies that Alison DiLaurentis (Sasha Pieterse) has something to hide. What is it?

She killed someone.

We still don’t know who is currently residing in Ali’s grave (because it’s not Ali) and how she got there. We don’t want to think that Alison is capable or murder...but is she? Hey, maybe it was accidental. Maybe Ali inadvertently killed someone, and then faked her own death so she wouldn’t have to go to jail for it. There are probably easier ways to deal with this sort of thing, but teenagers brains are still forming or whatever. This would certainly explain why Ali didn’t go to the police after someone “tried to kill her.” It might also explain why Mrs. DiLaurentis is acting so shady about whatever (i.e. inadvertent murdering) went down at Radley: she’s protecting her daughter.

She has a baby.

The summer before she took off, Alison supposedly thought she was pregnant — at least that’s what CeCe claims her bestie told her. Later, Mona shows Spencer the pages in Ali’s diary that say it was just a scare, implying Alison was never pregnant. Could those pages have been doctored? Or could Alison have purposefully lied when writing in them? Spencer called Ali’s diary “creative non-fiction with pseudonyms.” Did Ali get “creative” in this instance? A pregnancy might explain why Alison ran off, and why she’s stayed away: so that she could have the baby without anyone knowing about it. It might also explain why Ezra is so desperate to find her: he might be the father. (It also explains as why the show insisted on giving us the Malcolm and Maggie subplot, which seemed to serve no purpose, other than temporarily breaking Ezria up.)

She has a twin.

There’s always the twin theory! It happened in the books, and there have been many a twin clue in Pretty Little Liars’ run thus far. We’re not sure how the confession that Alison has/had a twin will play into the story of the night Alison disappeared, but it could be vital. Did Spencer go after the wrong DiLaurentis, and really kill her? Regardless, is it Ali’s twin who is in the grave? Is it Ali herself, and her twin is the one who has been contacting the Liars? This reveal would totally confuse everything we already know for certain about the “A” game (which, admittedly, isn’t a lot), but it might be worth it…

What do you think Alison is hiding? Share your theories in the comments below!

Catch the next episode of Pretty Little Liars on Tuesday, March 11, 2014 at 8 p.m. ET on ABC Family.

Kayti Burt is a contributing writer for Wetpaint Entertainment with a penchant for all things pop culture. Follow her on Twitter and Google+!