Thomas Farriner, the humble baker who was the supposed cause of the fire, is played by Andrew Buchan, and in this story he's a widower with two daughters and is in love with his brother's wife, Sarah.
But Sarah's caught the eye of Lord Denton, the fierce intelligence officer of the King, and when she finds herself thrown in prison just as the fire begins to spread, Thomas faces a choice between getting his family to safety or saving Sarah.
With the fire moving quickly and destroying London, the authorities must act quickly, but will the cowardly King Charles II step up and save his capital city – or will he let it burn?
The Great Fire, ITV, 9pm
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