Electrons moved in two dimensions when influenced by a magnetic field, hinting at how a similar effect would occur in the fourth dimension.

For the scenes inside the Palace Theatre, the conductor of the orchestra is played by Dudley Simpson, the composer of the incidental music for this and many other Doctor Who stories of the 60s and ...

This concept was repeated in the Fourth Doctor’s final story, Logopolis, in which the Master materialises his ship around (and inside!) the Doctor’s. Trapped in a prison cell together ...