The CW has released the synopsis for the first post-hiatus episode of The Flash, and it's filled with family drama and danger on all fronts.

The April 21 episode, titled "So Long and Goodnight," will see problems revolving around Black Hole intensify as the slippery contortionist Ragdoll returns with his sights set on Joe West.

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In addition to this, we'll get more information on Sue, Ralph Dibny's future partner in crime-solving. Meanwhile, Iris, who's stuck in a mirrorverse, will question what Eva's true motives are, given her husband Joseph's connections to Black Hole.

The CW's official synopsis for "Son Long and Goodnight" is below:

BLACK HOLE THREATENS JOE’S LIFE – After Black Hole hires Rag Doll (guest star Troy James) to kill Joe (Jesse L. Martin), Singh (guest star Patrick Sabongui) suggests he go into Witness Protection but Joe refuses to stop investigating Carver (guest star Eric Nenninger). While investigating Carver with Cisco (Carlos Valdes), Ralph (Hartley Sawyer) runs into Sue (guest star Natalie Dreyfuss). Iris (Candice Patton) becomes suspicious of Eva (guest star Efrat Dor). Alexandra La Roche directed the episode written by Kristen Kim & Thomas Pound (#616). Original airdate 4/21/2020.

Airing Tuesdays at 8 p.m. on The CW, The Flash stars Grant Gustin, Candice Patton, Carlos Valdes, Danielle Panabaker, Tom Cavanagh, Jesse L. Martin, Danielle Nicolet,and Hartley Sawyer.

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