An ambitious blend of fact and fiction, fantasy and reality, telling the story of Mary Godwin's marriage to Percy Shelley and creating an allegory in which the story of Frankenstein serves as a metaphor for their disturbed relationship.

Timelines are blurred as Godwin miscarries Shelley's baby, immediately followed by the suicide by drowning of Shelley's first wife, then the birth and early death of Mary's child William and Shelley's affair with Mary's step-sister Claire, leading to the poet's own death.

The central idea of the Frankenstein tale growing from Mary's psychosis is a good one, and the screenplay does well to integrate so many factual elements into a reasonable storyline, but this is also partly the film's undoing. A simpler telling would have worked better, without the shifting allegiances between Shelley, Mary, Claire and Lord Byron distracting from the plot.

Bravely, the script does not try to sugarcoat any of the characters. The literary couple are volatile, jealous, self-centred and spoilt. The romance is no fairytale, and the child death is harrowing. Laudanum contributes to the paranoia and mistrust between the characters, but ultimately the audience is left with no clear sense of what has happened. Too many liberties and inventions simply cause confusion and the film fails to convince.