Part three of the upcoming CW "Crisis on Infinite Earths" will bring two new faces into the Arrowverse proper.
According to the synopsis for "Crisis on Infinite Earths: Part Three," which takes place on The Flash, both Cress Williams' Jefferson Pierce/Black Lightning and Osric Chau's Ryan Choi/Atom will join the rest of the heroes in their battle to save the Multiverse from the Anti-Monitor.
The CW's official synopsis for "Crisis on Infinite Earths: Part Three" is below:
THE FLASH
"Crisis on Infinite Earths: Part Three" — (8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV)
BLACK LIGHTNING JOINS THE ARROWVERSE IN THE THIRD CHAPTER OF THE CROSSOVER – Pariah (Tom Cavanagh) enlists Black Lightning (guest star Cress Williams) to help stop the Anti-Monitor (guest star LaMonica Garrett) after Flash-90 (guest star John Wesley Shipp) shares what he learned from his battle in ‘Elseworlds.’ With the help of Black Lightning, Barry (Grant Gustin), Cisco (Carlos Valdes) and Killer Frost (Danielle Panabaker) come up with a plan that could save them all. Meanwhile, Iris (Candice Patton) has a heart-to-heart with Ryan Choi (guest star Osric Chau), while Oliver (guest star Stephen Amell) and Diggle (guest star David Ramsey) return to an old familiar stomping ground. David McWhirter directed the episode with story by Eric Wallace and teleplay by Lauren Certo & Sterling Gates (#609). Original airdate 12/10/2019.
"Crisis on Infinite Earths" begins Sunday, Dec. 8 on Supergirl, then continues in Batwoman on Monday, Dec. 9, and then picks up in The Flash on Tuesday, Dec. 10. After a winter hiatus, the crossover concludes on Tuesday, Jan. 14 on both Arrow and DC's Legends of Tomorrow.