“Pretty Little Liars” dropped an awesome bombshell at the end of Tuesday’s (July 19) episode when Noel Kahn (Brant Daugherty) strolled into Radley to meet up for drinks with Jenna (Tammin Sursok) and Sara (Dre Davis). And while that’s an evil threesome we will gladly watch wreak havoc on Rosewood, it still wasn’t the most telling part of “Along Comes Mary.”

The most telling part of the episode was when Aria (Lucy Hale) and Emily (Shay Mitchell) broke into Rollins’ (Huw Collins) “burner apartment” and found a copy of “Twelfth Night.” The camera zoomed in on the Shakespeare play, which means it can’t be a throwaway reference. And actually, a lot of what has happened on “Pretty Little Liars” lately is like a gender-reversed “Twelfth Night.”

A ‘Twelfth Night’ break-down

In “Twelfth Night,” there are twins named Viola and Sebastian who are separated by a shipwreck. It’s not a stretch to see that they represent Charlotte (Vanessa Ray) and Alison, separated by Charlotte nearly drowning Alison in the bathtub (albeit accidentally). But the hints that Alison had a twin have been part of “PLL” since very early on and that “twin” turned out to be Charlotte.

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In the play, after the shipwreck, Viola dresses up like a man, Cesario, to enter the service of Duke Orsino. While working for the duke, Cesario (who is really Viola) falls in love with the duke. The duke, meanwhile, is in love with Olivia and Olivia ends up falling in love with Cesario.

When Sebastian reappears, Olivia marries him after mistaking him for Cesario. It fits “Pretty Little Liars” — Olivia is in love with Viola (Cesario) but marries Sebastian instead, like Rollins is in love with Charlotte but married Alison instead.

Yes, it’s a bit sticky that Viola is merely pretending to be a man, while Charlotte was transgender, but it still works as a gender-reversed “Twelfth Night.” The only question is, who’s the duke?

The Duke

Based on the “PLL” parallel with “Twelfth Night,” the duke should be a female character who is in love with Rollins and with whom Charlotte was secretly in love — but that really narrows down the choices. Sara Harvey seems like the likeliest candidate. Maybe Rollins was in love with Charlotte, but Charlotte wasn’t in love with Rollins. We have no proof she was. Maybe Charlotte secretly loved Sara and that’s why they were working together?

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However, there’s also a working theory that Wren (Julian Morris) is connected to Rollins — so what if they’re the twins, Viola and Sebastian? Rollins is Viola by virtue of the fact that he pretended to be something he’s not. That would make the duke = Charlotte, but who’s Olivia? Melissa? Alison?

Or what if Mary and Jessica (Andrea Parker) are the twins, with Mary being the one pretending she’s someone else? So does that make Kenneth DiLaurentis (Jim Abele) the duke? Mary’s in love with Kenneth, Kenneth’s in love with … but that doesn’t work because Jessica would be Sebastian, not Olivia.

It gets a lot murkier if you try to imagine other scenarios. And none of them fit the play as well as the first theory. But it’s some good food for thought going into the back of “Pretty Little Liars” Season 7a.