Arrowverse executive producer Marc Guggenheim has been teasing fans all week with tiny glimpses of the upcoming four-show crossover event. However, until today, most of the teases were so cryptic, there was really no way to decipher what they actually meant.

Today, though, Guggenheim tweeted out a photo of a mask that is apparently from the Legends of Tomorrow chapter of the crossover, and it looks suspiciously familiar.

Eagle-eyed fans have suggested this could be the mask of long-running DC character, Sandman.

No, not the character from Neil Gaiman’s acclaimed Sandman series. We’re talking about the original Golden Era Sandman.

More specifically, it looks like the mask that belonged to Sandy Hawkins, the sidekick of the original Sandman who eventually took over the mantle himself and became a prominent member of the Justice Society of America.

The JSA played a major role in Season 2 of Legends and with Vixen still on the team, it stands to reason the show could return to the group at some point.

Also, it’s worth mentioning that a gas mask belonging to the original Sandman, Wesley Dodds, has been present as an Easter egg onboard the Waverunner, but this mask more closely resembles the one worn by Hawkins.

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Then again, this could be just a new mask for Heat Wave or some background player with no major significance on the story. Who knows?

The two-night Supergirl/Arrow/Flash/Legends crossover event will air November 27 and 28 on The CW. needs writers! Click HERE for more information and learn how to apply!

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Who do you think this mysterious mask belongs to? Would you welcome an appearance from the original Sandman or his ward? Tell us what you think in the comments below!