David Cubitt

Arrow has added yet another DC Comics character for its upcoming third season.

Medium's David Cubitt has been tapped to guest-star as Mark Shaw, otherwise known as Manhunter, TVGuide.com has confirmed. Shaw is an A.R.G.U.S. operative in Corto Maltese who crosses paths with Diggle (David Ramsey).

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Cubitt joins the long list of stars coming to Arrow in Season 3, including Brandon Routh, Charlotte Ross, J.R. Ramirez, Karl Yune, Devon Aoki and Peter Stormare. The series has not yet cast the highly anticipated new villain Ra's al Ghul.

The news was first reported by The Hollywood Reporter.

What do you think of the casting? Who would you like to see play Ra's al Ghul? 

Arrow returns for its third season on Wednesday, Oct. 8 at 8/7c on The CW.

(Full disclosure: TVGuide.com is owned by CBS, one of The CW's parent companies.)