Echo kellum will be playing Curtis Hoult. It is understood that he will be working with Felicity Smoak.
In comic books, Mr. Terrific is Michael Holt, a brilliant olympic athlete who becomes a hero after the death of his wife and child. In Arrow, EW describes Holt as an inventor who works for Palmer Technologies under Felicity Smoak. It was also revealed at SDCC that this version of Mr. Terrific will be gay.