Manchester, 1919.

To Detective Chief Inspector Frank Tinsley, it initially appears to be a straightforward crime. A drunkard has been stabbed to death and robbed.

But what was a drunk man doing behind the university physics building at three in the morning?

As Tinsley seeks answers, he becomes convinced that the key to solving the murder lies in the contents of a scientific notebook, mysteriously missing since the battlefield death of its owner, Henry Moseley, a brilliant young atomic physicist who died in the Great War.

But Tinsley is not the only one searching for the notebook. German Intelligence believes it contains the secret to a devastating new kind of weapon, and has sent an IRA operative, Graham Donnelly, to retrieve it, promising rifles and ammunition in return. Donnelly, half-English, is desperate to prove himself a patriotic Irishman and will allow nothing to stand in the way of completing his assignment.

As Tinsley becomes aware of the deadly potential of the notebook's contents, he realises that the stakes are higher than he could possibly have imagined.

Should he fail, the notebook and its atomic secrets will fall into the hands of Germany, just at the time a young Adolf Hitler is plotting his rise to power.