Series taking viewers on a journey through time and space to relive action from the legendary sci-fi show, featuring exclusive interviews with key actors offering unique insights. The Doctor has met his fair share of alien enemies. From giant wasps to squat Sontarans, he has come up against the finest in the universe. David Tennant and other cast members discuss some of the most memorable monsters and talk about a selection great alien moments. Narrated by Jo Whiley.