David Tennant and Billie Piper are gearing up to star together again in Doctor Who for a special anniversary episode after 17 years.The Harry Potter alum played

With Doctor Who’s explosive May 31 series finale majorly hinting at Billie Piper taking on the iconic role of the Time Lord, fans may be stunned at what the actress once said about women playing the famous protagonist.

As we ponder just who Billie Piper could be playing now (oh, we have theories ), below, we take a look at 10 episodes (all streaming on HBO Max) you should watch now that she’s back on Doctor Who. This episode and one word (“Run”) are what started it all.