"Whats with the Poice Box?"
The Doctor explains why the TARDIS looks like a police box.
Dinner with a Slitheen
The TARDIS crew take a holiday, but the Doctor encounters an enemy he thought long since dead. A plan to build a nuclear power station in Cardiff City disguises an alien plot to rip the world apart. And when the Doctor dines with the Slitheen impersonating Margaret Blaine - now the mayor of Cardiff - he discovers traps within traps.
The heart of the TARDIS
Margaret takes Rose hostage and demands the extrapolator. The heart of the TARDIS opens on the console, bathing Margaret in light. While she is captivated by the light, Jack and the Doctor close the rift and disable the extrapolator. As the console closes, they find that Margaret's human suit is empty except for a Slitheen egg.