NBC has released this description in addition to some preview images for the episode, which is called “Project Reborn.” First, here’s the synopsis:
IN THE FIERY FINALE, THE HEROES UNITE TO SAVE THE WORLD — NOAH GRAY-CABEY, JIMMY JEAN-LOUIS AND CRISTINE ROSE GUEST STAR — As the clock counts down to the end of the world, Tommy (Robbie Kay) finds himself up against his biggest challenge yet as Erica (Rya Khilstedt) takes drastic measures to see her plan succeed. Malina (Danika Yarosh) tries to fulfill her great-grandmother’s prophecy to save the world with the help of Luke (Zachary Levi) and Quentin (Henry Zebrowski). Meanwhile, Emily (Gatlin Green) and Ren (guest star Toru Uchikado) desperately search for Miko (Kiki Sukezane). Elsewhere, Carlos (Ryan Guzman) is faced with a life and death choice. Toru Uchikado, Hiro Kanagawa, Krista Bridges, Aislinn Paul, Nazneen Contractor and Lucius Hoyos guest star.
You can find some preview images below.