Colin Campbell Norris was born on February 12, 1976, in the Milton area of Glasgow, Scotland. He grew up in this neighborhood and lived there until he pursued further education. After finishing college, he began working as a travel agent. However, after a few years in that role, he decided to retrain as a nurse.

In nursing school at the University of Dundee, Norris had an average academic record. He found himself in conflict with his tutors and colleagues. His behavior was often described as aggressive, and he faced several confrontations during his time in education. One of his tutors noted that he frequently argued with her. Norris himself admitted that he did not get along with her, claiming there was a personality clash.

While studying, he learned about Jessie McTavish, a nurse convicted of murdering a patient with insulin years earlier. This incident occurred at Ruchill Hospital, which was not far from where Norris had grown up. During his studies, he was even tasked with reviewing McTavish’s conduct, which would later be seen as influential in his own life.

Norris began his nursing career in Leeds after qualifying in June 2001. Almost immediately, he had trouble getting along with experienced staff members. He expressed a strong dislike for working with elderly patients, stating that he found them challenging. Colleagues described him as someone who wanted excitement in his job and preferred the emergency department over caring for elderly patients.

Throughout his early career, there were signs of his troubling behavior towards vulnerable patients. Colleagues reported instances where he mistreated elderly patients, showing a clear disdain for them. His former partner recounted incidents of violence in their relationship, which led to their separation.

Colin Campbell Norris, a nurse, was involved in a series of incidents leading to the deaths of several elderly patients at two hospitals in Leeds. After only one year as a qualified nurse, Norris worked at Leeds General Infirmary and St James's University Hospital. He became a suspect following a disturbing prediction about one patient's decline.

On 11 December 2002, Norris predicted that Ethel Hall would become unwell at 5:15 a.m. He voiced this prediction to a colleague, claiming he had a feeling about her condition. Hall, a patient recovering from a fractured hip, did not show any signs of deterioration. However, she fell seriously ill around the predicted time and later died. A blood sample taken from Hall showed an extraordinarily high level of insulin, which led to police involvement.

Investigators later discovered that insulin had been taken from the hospital storage fridge, and Norris had accessed it shortly before Hall’s illness. This raised questions about his involvement. Following Hall's death, the hospital reviewed the cases of 72 patients who had died while Norris was on duty, uncovering further suspicious incidents.

Among the previous cases, three other women were found to have died from overdoses of insulin. Investigators determined that all these patients were non-diabetic and had only minor conditions, making the insulin injections suspicious. Norris was the only staff member on duty when these patients experienced sudden hypoglycaemic episodes. Crucially, he had been the last nurse to see each of them before their health declined.

Despite denying any wrongdoing, Norris's past behavior came into scrutiny. He had a history of mistreating elderly patients and was known for his dislike of them. On multiple occasions, he had injected patients with unnecessary medications, which did not follow medical protocols. His actions and the patterns of illness being directly linked to his shifts led to a thorough police investigation.

In March 2008, Norris was convicted for the murders of four elderly women and the attempted murder of another. He received a life sentence with a minimum of 30 years in prison. His case raised many concerns about hospital procedures and the safety of vulnerable patients. Following his conviction, there were claims of other potential victims, but insufficient evidence prevented further charges. Colin Norris remains in prison, with ongoing discussions about the implications of his actions still resonating in the medical community.