Jared Harris Jared Harris

The filming of Mad Men's third season just began Monday, and there's already a new face in the Sterling Cooper office.

Jared Harris has joined the acclaimed AMC drama for a 10-episode arc, TVGuide.com has confirmed. Harris will play Lane Pryce, Sterling Cooper's financial officer.

Harris recently appeared in a guest arc on Fringe and in the Oscar-winning film The Curious Case of Benjamin Button. The British actor also just signed on for an untitled CBS Films project starring Harrison Ford and Brendan Fraser, on which he will work simultaneously with Mad Men.

As previously reported in TVGuide.com's Mega Buzz, Mad Men is slated to return in August. AMC has yet to confirm a premiere date.