The Flash managed to slow things down a bit for Kevin Smith’s emotional “Runaway Dinosaur,” but all hell breaks loose in Central City by the looks of next week’s penultimate Season 2 outing “Invincible.” In addition to an Earth-2 Laurel on the loose to unleash her inner Siren, a whole army of colorful (and familiar) baddies have taken to the streets.

Not only does Katie Cassidy return from her Arrow demise to introduce us to Earth-2's Black Siren (who actually has the comic’s natural Canary Cry), but so too do we see the forces of Zoom causing absolute chaos for Central City. We’ll overlook a pair of apparently winged threats (we’d probably have heard about that kind of crossover), but does anyone else spy any other familiar faces?

So reads the synopsis for next week’s “Invincible”:

KATIE CASSIDY GUEST STARS AS BLACK SIREN

After Zoom (guest star Teddy Sears) unleashes an army of Earth-2 meta-humans on Central City, Barry (Grant Gustin) is shaken when he sees their leader is the Black Canary’s Earth-2 doppelganger, the Black Siren (guest star Katie Cassidy). Meanwhile, Wally (Keiynan Lonsdale) takes to the streets to help The Flash stop the meta-humans, which worries Joe (Jesse L. Martin). Iris (Candice Patton) and Henry (guest star John Wesley Shipp) are concerned about Barry taking on Zoom.

While we wait, check out the latest trailer again above, and stay tuned for more on the final Flash Season 2 episodes.

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