Simon finds out that the sun doesn't always shine in Italy and there is always a warm welcome when you're the Saint and hot on the trail of a gang of racketeers who intend to seek revenge.
After relaxing at a Roman villa the Doctor is mistaken for a murdered lyre player and targeted by an assassin. Meanwhile, Ian and Barbara are captured by slave traders.
Barbara is sold as a slave and Ian is to be trained as a gladiator.
Inspired by the Doctor, Nero sets Rome ablaze. Ian must fight his way out of the arena and rescue Barbara. The Doctor and Vicki hurry to flee the city and escape to the TARDIS.
Poppaea plans to poison Barbara who has become the object of Nero's affections. The Doctor is to be thrown to the lions, Ian and Delos are set against each other in the arena.
