CW Synopses May 7-10

The CW has released descriptions for their shows airing in three weeks.

Supergirl 3x17 "Trinity"

SUPERGIRL TAKES ON ALL THREE WORLDKILLERS – Still reeling after learning about Lena’s (Katie McGrath) secret, Supergirl (Melissa Benoist) asks Guardian (Mehcad Brooks) for a favor that could alter his relationship with Lena forever. Meanwhile, with all three Worldkillers united, Supergirl and the team brace for an epic battle. Caitlin Parrish & Erica Weiss directed the episode with story by Jessica Queller and teleplay by Caitlin Parrish & Derek Simon (#317). Original airdate 5/7/2018.

The Flash 4x21 "Harry and the Harrisons"

THE TEAM TURNS TO AMUNET BLACK FOR HELP — With DeVoe’s Enlightenment device nearly complete, in order to disable it The Flash (Grant Gustin) and his team must put their faith in an unlikely ally – Amunet Black (guest star Kattee Sackhoff). Meanwhile, Harry (Tom Cavanagh) hits an all-time low when the “Council of Wells” kicks him out but then Cisco (Carlos Valdes) introduces him to the “Council of Harrisons.” Kevin Mock directed the episode written by Judalina Neira & Lauren Certo (#421). Original airdate 5/8/2018.

Arrow 6x22 "The Ties That Bind"

DIAZ AIMS FOR TEAM ARROW AND THEIR FAMILIES — Diaz (guest star Kirk Acevedo) targets Team Arrow and their loved ones. Oliver (Stephen Amell) struggles with Felicity (Emily Bett Rickards) putting herself in danger when she gets the chance to stop Diaz for good. Tara Miele directed the episode written by Ben Sokolowski & Oscar Balderrama (#622). Original airdate 5/10/2018.

Supernatural 13x22 "Exodus"

HITCHING A RIDE – Sam (Jared Padalecki) and Dean (Jensen Ackles) devise a plan that will save innocent lives. Meanwhile, Jack (Alexander Calvert) continues to wrestle with the consequences of his decisions. Thomas J. Wright directed the episode written by Eugenie Ross-Leming & Brad Buckner (#1322). Original airdate 5/10/2018.