Laurel Lance actress set to appear as the Earth-2 version of her character, otherwise known as Black Siren!

More cross-program synergy is in the works for the Arrowverse, as EW reports that Katie Cassidy will be joining The Flash for Season 2’s penultimate episode.

In a twist, though, don’t expect Laurel Lance to just drive up the interstate for a visit to Central City. Nope, Arrow executive producer Marc Guggenheim says:

“You will see her on an episode of The Flash playing the Earth-2 version of Laurel Lance.”

It seems The Flash will continue its tradition of having Earth-2 represent a sort of Golden Age version of the DC multiverse, with Cassidy playing Black Siren (aka Donna Nance), a character originally created for Cartoon Network’s 2001-2004 Justice League animated series.

Black Siren was actually based on the Golden Age version of Black Canary, just given a new name and identity for the JL series. It’s pretty cool to see The Flash producers picking up an obscure reference for their Earth-2 Laurel Lance, though.

There’s no word yet on how big Cassidy’s role on the episode will be, but considering it’s the last episode before the season finale, it’s likely to be a fairly action-packed episode.

In the same story, EW also reports that Cassidy will lend her voice to the second season of the animated Arrowverse spin-off, Vixen. The WB Seed show was recently renewed for another round of episodes, following actress Megalyn Echikunwoke’s appearance on Arrow (“Taken”) in the Vixen role.

Arrowverse Crossover: "Crisis on Earth X"

This is all definitely cool news for Katie Cassidy/Laurel Lance fans, though it may be bittersweet. (Spoilers!) Recent rumors have suggested that it may be Laurel Lance in the ominous grave teased all throughout the fourth season of Arrow.

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