Doctor Who: 10 Best NuWho Guest Stars Ever

Lindsay Duncan appeared in the 2009 episode The Waters of Mars as Adelaide Brooke, the astronaut in charge of Bowie Base One. Tough and authoritative in the face of unbeatable odds in the form of a space virus, Adelaide was nevertheless willing to question the Doctor's ethics and actions, going so far as to kill herself to set time on the right road and stop him from becoming the self-proclaimed Time Lord Victorious.

This sense of strength and authority is the backbone of Duncan's performance. It's the basis for what makes the character such a good foil for David Tennant's Doctor within the episode and creates a believability to the way Adelaide challenges and later critiques him. It also allows for a number of other traits to come to the fore - an element of jadedness, for example, as if she is a bit wearied by command and by the situation she has ended up in.

While Duncan does all of this brilliantly, just doing those traits on their own would make for a very one-note performance. However, viewers get to go deeper into Adelaide's character, seeing what motivated her from childhood. Lindsey Duncan plays those scenes with a nostalgic warmth, making the character feel utterly three dimensional and earning the sympathy of viewers. And, incidentally, a place on this list.