'If anyone tries to interrupt this opening of Parliament, there'll be fireworks!'

London, November 1605. The TARDIS materialises at a crucial moment in British history. While Ian and Barbara set off for the Globe Theatre, Vicki accompanies the First Doctor on a mysterious mission to the court of King James.

What connects the King's advisor Robert Cecil with the sinister hooded figure known only as 'the Spaniard'? Why is the Doctor so anxious to observe the translation of the Bible? And could there be some dastardly plot brewing in the cellars of the Houses of Parliament?

As a history teacher, Barbara thinks she knows what to expect when she encounters a man called Guy Fawkes. But she is in for a very unpleasant surprise.