Here’s some Terrific news for fans of Arrow‘s Echo Kellum.

Fresh off of the episode in which Palmer Tech whiz Curtis Holt stumbled upon the Arrowcave, er, “bunker” and its many secrets, Kellum has been promoted to series regular status, effective with Season 5 (premiering this fall).

Kellum made his debut on the CW series in Season 4’s second episode, as the genius developer who has helped CEO Felicity Smoak keep Palmer Tech afloat.

The actor’s pre-Arrow TV credits include Ben and Kate, Sean Saves the World and You’re the Worst.

Arrow continues Season 4 this Wednesday with its 18th episode, “Eleven-Fifty-Nine,” in which Oliver and Diggle find out Malcolm wants to break Darhk out of prison and Laurel gets a surprising offer.

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