A threatening letter sent to the Prime Minister puts the British people in grave danger. The terrorist group John Amend-all are demanding that the government increases its aid to Africa, or they will release a deadly smallpox virus provoking a national epidemic. The Smallpox Containment and Reaction Unit (SCRUB) operation is launched. Dr. Herry Smith is called away from his day job as Medical Director of Public Health to help. Teaming up with Detective Inspector Rebecca Hale, the pair combine their medical and investigative skills in a bid to crack down on the culprits. But time quickly starts to run out, and before they know it hospitals start to fill with victims of the deadly virus. 

Dr Fraser Callan is recovering from his wife’s death. In need of a change, he takes a job at the Wansborough Community Hospital in Wiltshire. Previously known as St. James’, the hospital has made a miraculous recovery from a scandalous history, when it was described as “Death Wards” for the elderly by the national press. But history sometimes comes back to haunt us…At first, the hospital seems a model of excellence, but then Fraser realises that more patients are dying of pneumonia than should be the case. When he raises the matter, he is ridiculed, threatened with the sack and finally beaten up by gangs of thugs. Then, after the suspicious death of an old man with terminal cancer, Fraser realises he must act. He reports his suspicions and is persuaded by Marcus Evans, a mysterious civil servant, to work undercover to find the killer.

Latchvale Hospital. Sister Josephine Farewell  has suspicions about the deaths on her ward. As another patient dies unexpectedly, Sister Farewell begins to suspect that a serial killer is at work in the Intensive Therapy Unit. After reporting her fears to the police, Home Office investigator Tom Jones enlists Jo’s help in his undercover operation. Jones is not convinced that the deaths are random. But what is the link?As Jones and Sister Farewell investigate they find sinister connections between the patients that lead them into a world of religious fanaticism and cold-blooded manipulation…