Doctor Who: Time and the Rani

In his post-regenerative confusion the Doctor is separated from his young companion Mel and tricked into assisting the Rani in her megalomanic scheme to construct a giant time manipulator.

Lost on the barren surface of the planet, Mel has to avoid the Rani's ingenious traps and her monstrous, bat-like servants, the Tetraps. She joins forces with a rebel faction among the Lakertyans, desperate to end the Rani's control of their planet.

The Doctor must recover his wits in time to avoid becoming a permanent part of the Rani's plan to collect the genius of the greatest scientific minds in the Universe...