When writer Tom Leyland purchases a lovely old stone cottage in the Cotswolds he expects it to become a peaceful haven where he can relax and work on his latest novel, while at the same time getting over a recent broken relationship. Instead he stumbles onto a stairway into the past and discovers five doors which result in Tom and his new-found friend Kate, a middle-aged amateur historian and linguist, first visiting Britain in pre-Roman and Roman times and then travelling to both Norman and Elizabethan England. Opening the last door embarks them on an adventure set in the days of Nelson's triumph at Trafalgar, with life changing results for a number of people.