An Incompatible Passion tells the dramatized history of the last three months in the life of the controversial poet, Percy Bysshe Shelley. In the spring of 1822, Percy and his second wife, Mary Woolstonecroft, the author of the famous novel "Frankenstein," along with her half-sister, Claire, rented a villa on the Tuscan Coast. They were joined there by Jane and Edward Williams, and later the Cornish adventurer Edward Trelawny. The relationship between Mary and her husband soured after two of their three children died young. Both Mary and Claire shared Percy's affections, which caused tremendous friction, as the poet had a tendency to pursue pretty women. Claire had given birth to illegitimate daughters by both Shelley and Lord Byron, so living together in the same house was not easy for Mary. Trelawny persuaded a friend to construct a yacht for the poet, and while sailing one day with Edward Williams, a sudden squall capsized the boat and both men drowned. The remains of Shelley's body were cremated on the beach in the presence of Byron and Trelawny.