Season four of Doctor Who brings the return of the Doctor's former-almost-companion, Donna Noble, who is portrayed by actress Catherine Tate.

Doctor Who is a popular science fiction program that features an alien Time Lord who travels through time in a blue police call-box called the TARDIS. He travels with human companions through time trying to solve problems, avoid major catastrophes and maintain a balance in the universe.

The most recent series of Doctor Who, which kicked off in 2005 and starred Christopher Eccleston as the Doctor, has spun-off two different series: Torchwood and The Sarah Jane Adventures. Both shows exist in the same universe and the main characters at one time or another had contact with the Doctor.

Doctor Who Season Four begins with bridge episode Voyage of the Damned, which originally aired in England on December 25, 2007. The first episode of the season premiers on April 5th, 2008, when Donna Noble calls upon her old friend, the Doctor, to help foil the dark plans of over-the-top entrepreneur Miss Foster.

Throughout the season, the Doctor will have two other companions as well. Many fans will rejoice as Billie Piper returns for three episodes to play Rose Tyler. Freema Agyeman will also return to play Martha Jones for five episodes.

• Original Airdate: December 25, 2007
• TV.com: Doctor Who Special Episode
  • At the end of Last of the Time Lords, a ship crashes through the side of the TARDIS, mid flight, and a life ring bearing the name 'Titanic' is thrown towards the Doctor...
• BBC: Doctor Who Special Episode
• IMDb: Doctor Who Special Episode
• Wikipedia: Doctor Who Special Episode

• Original Airdate April 5, 2008
• TV.com: Doctor Who Episode 43
  • "During an alien emergency in London, a woman called Donna Noble must search for an old friend who can save the day - a man named the Doctor."
• IMDb: Doctor Who Episode 43
• Wikipedia: Doctor Who Episode 43

• Original Airdate April 12, 2008
• TV.com: Doctor Who Episode 44
  • "The Doctor takes Donna back to Pompeii, on the day of the eruption of Mt. Vesuvius, and is faced with a great moral dilemma. Should they warn the residents of the impending disaster, or let history take its natural course?"
• IMDb: Doctor Who Episode 44
• Wikipedia: Doctor Who Episode 44

• IMDb: Doctor Who Episode 45
• Wikipedia: Doctor Who Episode 45
  • The Doctor discovers what drove the Ood to become a servant race.

• IMDb: Doctor Who Episode 46: (Two Part Episode)