The CW has revealed the first promo and images for episode 2.21 of "Arrow" which you can check out below, but if you're not caught up on the series, look away, because there are some spoilers! Titled "City of Blood," the episode is described as follows:

"After Slade threatens to take everything Oliver loves away, Oliver decides the fastest way to stop further bloodshed is to surrender to his enemy. Knowing that surrender will surely lead to Oliver’s death, Diggle and Felicity go to extreme measures to keep Oliver from confronting Slade. Meanwhile, Thea considers leaving town, and Laurel resumes her crusade against Sebastian Blood. Finally, Slade unleashes his assault on Starling City."

Directed by Michael Schultz from a script by Holly Harold, "City of Blood" is set to air April 30th. "Arrow" airs Wednesdays at 8 P.M. ET/PT on The CW.​​​​