The CW has released a new promo for next week's episode of "The Flash" -- titled "Invincible" -- that sees the debut of Earth-2 Laurel Lance (Katie Cassidy) as the Black Siren.

In the penultimate episode of Season 2, Black Siren leads Zoom's army of meta-humans from Earth-2, while Wally comes to Barry's aid to take on the assault on Central City.

RELATED: New "Flash" Poster Touts Zoom's Return 'With a Vengeance'

Check out the promo for May 17's "Invincible" below:

THE FLASH "Invincible" - (8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV)

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.  Jesse Warn directed the episode with story by Greg Berlanti & Andrew Kreisberg and teleplay by Brooke Roberts & David Kob (#222).  Original airdate 5/17/2016.

RELATED: "The Flash" Season Finale Synopsis Reveals a Showdown with Zoom

"The Flash" airs Thursdays at 8/7c on The CW.