With production getting under way on Season 4 of Arrow, The CW series has just added yet another new cast member, bringing aboard Echo Kellum to play Curtis Holt, a.k.a. Mr. Terrific. The actor will have a recurring role on this new season of Arrow, first appearing in the second episode. It isn't known how many episodes he has signed on for in total, or if there is an option for him to become a series regular in Season 5.

Entertainment Weekly describes Curtis Holt as a "technological savant and inventor," who works for Palmer Industries under the supervision of Felicity Smoak (Emily Bett Rickards). You may recall that, in the Season 3 finale, both Oliver Queen (Stephen Amell) and Felicity were seen driving away from Starling City together, supposedly starting a new life together. But it apparently doesn't take the couple long to go back home. It remains to be seen how long it will take for Curtis to transform into Mr. Terrific when Arrow Season 4 debuts this October.

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In the DC Comics, Mr. Terrific's true identity was Michael Holt, who first appeared in a 1997 issue of Spectre. Holt was mentioned in the comics as being the third smartest man on Earth, who has a knack for picking up complex skills instantly. He was also an Olympic athlete who joined the Justice Society of American after the death of his wife and unborn child. While he doesn't have any super-human abilities, he is aided by "T-spheres," small robotic devices which allow him to fly and can be used as weapons as well. Holt was actually the second person to take up the Mr. Terrific persona, following the Golden Age hero Terry Sloane.

Echo Kellum's casting comes just a few days after Neal McDonough signed on to play the primary villain in Season 4, Damien Dahrk. The show's cast and producers also revealed new costumes for both Arrow and Diggle (David Ramsey). Production is already under way, with Season 4 slated to debut on Wednesday, October 7.

Echo Kellum is best known for his roles in Fox's Ben and Kate and Sean Saves the World. He has also voiced a number of characters in Rick and Morty, and he most recently had a multi-episode arc on NBC's A to Z. What do you think about Mr. Terrific being cast in this upcoming season of Arrow? What DC Comics character do you think they should cast next?