Normally, no one would bat an eye at Arrow indulging in a little celebratory trip down memory lane for its 100th episode, but the hour’s placement in a four-way CW crossover changes the game just a bit. As such, a new photo from the centennial’s table read reveals a surprising guest star from the series’ past, whose presence opens up a whole new quiver of questions.

You’re warned of potentially major spoilers from here on out, but executive producer Marc Guggenheim shared a quick snap from Arrow’s 100th episode table read, featuring the majority of known Season 5 cast. That is, until you glance at the fellow just over Stephen Amell’s shoulder:

That would be actor Jamey Sheridan, otherwise known in the Arrow world as Oliver’s father, Robert Queen. Normally, we’d write off the appearance as another flashback, but Guggenheim specifically denotes that neither past memories, nor The Flash’s reality-bending “Flashpoint” changes have a hand in the Queen patriarch’s return.

So, what then could bring Robert Queen back into the fold, given his memorable suicide in the pilot episode? Well, there’s always the Robert Queen of Earth-2, who (in a nod to the comic Flashpoint) was revealed as the Green Arrow of that particular universe. It’s merely an option, but one that it imply at least part of the four-way crossover involves a trip to another Earth, or perhaps vice-versa. If not, those Legends do like their time-travel.

Stranger still, the blue script just in front of Amell has “Alex Zahara” splashed over the title page, that of a Canadian actor who played drug-dealer Anthony Venza in Season 1. Oliver took him down with the aid of Jessica de Gouw’s Helena “The Huntress” Bertinelli, but don’t get your hopes up for that return just yet.

Somehow, we imagine Sheridan won’t be the only notable guest star for Arrow’s 100th episode, but if Robert Queen is hanging around, might Moira be far behind? Or is Season 5 big bad Prometheus perhaps Oliver’s father, lending a mirror image to the series?

Arrow Season 5 will premiere on October 5, but stay tuned for the latest on the epic crossover.

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