23 October

On 23 October 1843, the Fifth Doctor, Tegan and Nyssa found themselves embroiled in a Sevakrill plot to destroy Earth with a missile, programmed to detonate in 2017. Climbing Nelson's Column, the Doctor found that both Samuel Morton Peto and Thomas Grissell had been possessed by the Savrakrill. Several stone lions were protecting the operation and killed seven civilians and a policeman while pursuing Nyssa and Tegan. The Doctor managed to appeal to Peto and Grissell and they forced their hosts out. With that, the stone lions resigned themselves to their plinths. (PROSE: The Lions of Trafalgar)

In 1829, the crew of the wrecked Mermaid was rescued by the Swiftsure. (PROSE: Of the Mermaid and Jupiter)