No longer will American TV audiences be asking doctor who?

Popular British actor David Tennant, best known for playing the title role in the BBC's long-running sci-fi series "Doctor Who," is set to make his American television debut as the title character in NBC's hour-long pilot "Rex Is Not Your Lawyer."

The comedic legal drama centers on a top Chicago litigator (Tennant) who begins suffering panic attacks and takes up coaching clients to represent themselves in court.

NBC green lighted the project in August, about two years after it was first developed, and had been trying to find a lead actor for several months until Tennant came along and nailed the part. Tennant, a theater and TV actor, rose to fame playing the mysterious alien time-traveler at the center of "Doctor Who" for the past five years. His performance as the Doctor has been often rated as the top in the franchise's 46-year history.

Tennant's casting is reminiscent of the tapping of another established British TV actor with virtually no American TV experience, Hugh Laurie, as the lead on Fox's medical drama "House."