The new Netflix documentary The Investigation of Lucy Letby offers new insights into the British serial killer’s gruesome crimes and features never-before-seen footage of Lucy Letby’s arrest.
Letby murdered sick newborns while working as a nurse at Countess of Chester Hospital in Chester, England. From 2015 to 2016, she targeted a total of 17 children in her care, injecting them with air bubbles and poisoning them with insulin. Following two trials, the now 36-year-old was convicted of murdering seven infants and attempting to kill seven others, for which she received 15 life sentences with no possibility for parole.
Despite her 2023 and 2024 convictions, however, Lucy Letby has firmly maintained her innocence, as have her parents, Susan and John Letby, who have staunchly defended their daughter every step of the way.
Susan and John Letby reportedly married in the mid-1970s and welcomed their only child, Lucy, in January 1990. They’ve lived in the same house in a close-knit community in Hereford, England, for more than 40 years.
Here’s what we know about Susan and John Letby’s lives—and their involvement in Lucy’s case.
How Did Susan and John Letby React to the Allegations Against Lucy Letby?
Just two months before authorities launched a formal investigation into the rise in infant deaths, Susan, now 64, and John Letby, 80, told police that Lucy was being made into a “scapegoat.”
The doting parents filed a report at the Blacon Police Station in March 2017, placing blame on consultant pediatricians Stephen Brearey and Ravi Jayaram, who were among the first to raise concerns about the former nurse. At the time, Lucy had been moved to administrative duties and was no long working directly with patients.
Prior to Lucy’s conviction, John allegedly threatened then-hospital CEO Tony Chambers during a December 2016 meeting about the allegations against his daughter. According to Chambers, he threatened to report Brearey and Jayaram to the General Medical Council (GMC).
“He was making threats that would have made an already difficult situation even worse by threatening GMC referrals for the doctors,” the former executive recalled during a public inquiry in November 2024. “He was threatening guns to my head.”
When that didn’t work, Susan and John later pleaded with Countess of Chester Hospital’s top executives to make the case for their only child’s innocence. “There is a saying ‘innocent until proven guilty’ but it doesn’t seem to apply to Lucy. She is still the only one of all the staff on the neonatal unit to be singled out for punishment,” Susan, a retired accounts clerk, and John, a retired furniture salesman, wrote in an email in July 2017.
“Whilst we appreciate that things cannot be finalized until the police investigation has ended we have to have a way of moving forward in terms of her career for however long the investigation takes.”
Were Susan and John Letby Surprised by Lucy’s Conviction?
During her trial, the couple temporarily moved from Hereford to Manchester, renting an apartment in the city center to be closer to their daughter during her trial. Susan and John attended nearly every day of the 10-month trial at Manchester Crown Court in 2023.
When the guilty verdict was finally delivered that August, Susan broke down in court, expressing surprise and outrage. “You can’t be serious. This cannot be right,” she reportedly said. But despite their frequent attendance, they notably didn’t show up to their daughter’s sentencing hearing, during which she was sentenced to life in prison without the possibility for parole.
Will Susan and John Letby Watch the New Netflix Documentary?
In the wake of Lucy’s conviction, Susan and John remain in close contact with their daughter and have continued to support her. In a statement to The Guardian in February 2026, they rebuked the new documentary about Lucy. The couple claimed that while any shows or programs about their child’s crimes are “heartbreaking,” Netflix’s The Investigation of Lucy Letby “is on another level.”
“We had no idea they were using footage in our house. We will not watch it—it would likely kill us if we did,” Susan and John wrote. According to the Letbys, the film includes “distressing” footage of Lucy saying goodbye to her cat before being hauled away in handcuffs in her pajamas. At the time, she had moved back in with her parents after she was removed from the neonatal unit.
“Heaven knows how much more they have to show. All this taking place in the home where we have lived for 40 years,” her parents added. “It is in a small cul-de-sac in a small town where everyone knows everyone. It is a complete invasion of privacy ... What we go through every day is nothing to what Lucy goes through but we still have to live here.”
How to Watch The Investigation of Lucy Letby on Netflix
The new Netflix documentary The Investigation of Lucy Letby examines the convicted killer’s crimes and divisive case through previously unheard insider accounts and never-before-seen video footage. The film is now streaming on Netflix.
Catherine Caruso joined the Biography.com staff in August 2024, having previously worked as a freelance journalist for several years. She is a graduate of Syracuse University, where she studied English literature. When she’s not working on a new story, you can find her reading, hitting the gym, or watching too much TV.
