This is Capaldi's third -- and final -- series. Capaldi has announced he will depart from the show at the end of series 10 at the same time as outgoing showrunner Steven Moffat. New showrunner Chris Chibnall will then debut a new Doctor.
"One of the greatest privileges of being Doctor Who is to see the world at its best," Capaldi said in his farewell announcement on BBC radio in late January. "I can't thank everyone enough. It's been cosmic."