London, 2007. Tom Jackman is the only living descendent of Dr. Jekyll and Mr. Hyde. During the night Tom becomes Mr. Hyde, but Tom's fighting back. The only question is: are all the resources of 21st Century surveillance technology enough to keep a Victorian demon in check? And can he keep his wife and children safe during the 'night shift'?

With Hyde emerging more and more unexpectedly, Jackman finds himself not knowing where he's been or what he's done. Jackman is also being deceived. His nurse Catherine is working for someone else as is a close friend. He is still being followed by the organization with the black vans, though it appears they are more interested in Mr. Hyde that in Jackman. They set up a terrifying confrontation at a local zoo that endangers Jackman's children. Jackman is not sure how, but Hyde starts to communicate with him directly for the first time. Finally, Jackman meets someone who may be able to tell him about his family history.

The battle of wits continues between Tom Jackman and Mr. Hyde. On the road for a week now, Jackman has taken to chaining himself up at night in order to keep Hyde from some of his excesses. The mysterious group following him continues in its attempt to kidnap him. Tom visits his old friend Paul Syme and demands answers only to learn that his employer, the Institute, existed for only one purpose: to study him. To his great surprise, his wife Claire is also there and she learns his secret and meets Mr. Hyde. When Tom awakens the next day, he again has no recollection of what Mr. Hyde has done.

Now back at the Institute with Tom incarcerated, Peter Syme is forced to speak to the private detective Claire had hired to follow Tom. The meeting is a revelation to Claire who learns that everyone knew of Tom's alter ego except her. The detective reveals her theory on the origins of the Institute and its true scientific purpose. In flashbacks, we learn how Tom Jackman and his wife Claire first met 7 years previously and of his early days at the Institute. Even then, there were subtle suggestions of Mr. Hyde's existence: a thumb print that isn't his, a sudden growth of hair on his arms or a violent, sudden rage when his wife is threatened.

With his condition now stabilized courtesy of the Insitute's cure, Mr. Hyde seems to have emerged as the dominant personality. He has however retained some of Tom's memories which come back to him in a flood. His memories also flashback to 1886 Edinburgh, where we see Dr. Jekyll meeting his fiend Robert Louis Stevenson who has written a fictional tale based on his experiences. Stevenson has also correctly guessed the nature of Jekyll's secret 'potion' which is revealed to the modern day Mr. Hyde. Claire is surprised when Hyde proposes something completely unexpected.

With the re-emergence of Tom Jackman, he and Hyde join forces to free Claire and the children who are under guard. Tom learns the details of the project from Peter Syme who tries to justify what they have done but again, Tom is betrayed. Claire finally learns Tom's family history when she meets Tom's mother. She also learns some important information about herself. There is one final puzzle however, for Tom to resolve.