Original sentence: The programme depicts the adventures of a mysterious alien time-traveller known as "the Doctor"(currently Matt Smith) who travels in his space and time-ship, the TARDIS, which normally appears from the exterior to be a blue 1950s police box
Edited sentence: The programme depicts the adventures of a mysterious alien time-traveller known as "the Doctor" who travels in his space and time-ship, the TARDIS, which normally appears from the exterior to be a blue 1950s police box