The Doctor meets Belinda Chandra and begins an epic quest to get her back to Earth. But a mysterious force is stopping their return and the time-traveling TARDIS team must face great dangers, ferocious enemies and wilder terrors than ever before.

After saving each other from jumping off a bridge, Henry Bell and Karen Knightly plot to avenge the people who drove them to suicide. Henry will ruin the life of the woman who married Karen's boyfriend, while Karen will work as a secretary for the man who took Henry's job. Whether revenge will be sweet – or bittersweet – is anyone's guess.