Matt Smith, age 26. Pretty much an unknown. Set to be the next Doctor when series 5 starts in 2010. The new series will be produced by Steven Moffat (Hugo award winning writer of the Doctor Who).
*note, this is just a promo photo, the Doctor's new attire hasn't been selected yet.
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Here's an interview with him on Doctor Who confidential. John and I kind of see him as British Nathan Fillion type, which is a good thing. He does NOT appear 26, and is really be excited about taking the roll.
Lyn