Life seems full of promise for Sophie Devine, young wife and mother of two. But it is 1665 and, as spring gives way to summer, the shadow of plague hangs over London.

When the city is finally stricken, Sophie is offered a safe haven for herself and the children on her brother's farm in Woolwich. Fanny, their maid is left behind in London to care for her master, but discovers that Matthew is in love with someone else.

Stunned by the knowledge of his infidelity, Sophie is forced to return to a London now ravaged by sickness and death to try and win back his love - and finds herself also fighting for his health, and her own feelings for Luke Meredith, on of the few dedicated doctors to remain in the beleaguered city.