Mobile phone data uncovered a chilling exchange that became a key piece of evidence after a much-loved mum was found murdered in her Hampshire flat08:11, 01 Aug 2026A killer sent a chilling seven-word text message to a much-loved mum just minutes before he arrived at her flat and brutally strangled her.‌Channel 4's The Digital Detectives revisits the killing of Samantha Holden, 56, who was found dead at her flat in Farnborough, Hampshire, in September 2022 after being suffocated and strangled by Adam Watson.‌The programme reveals how mobile phone data helped investigators establish Watson's movements and his contact with Ms Holden in the hours before her death.‌Just before the fatal attack, Watson sent Ms Holden a message at 12.44pm saying: "Joanna I am 30 seconds from your door x." She replied moments later: "come up x".Explaining the significance of the messages, higher analyst Elaine Lucas says in The Digital Detectives: "When we download the data from Watson's phone, we found texts between Sam and Watson on the day of her death.‌"Watson doesn't refer to Sam by her name, he calls her Joanna. Digital media confirmed that, despite his 'no comment', he was the client. Sam had seen Adam Watson before, on at least three occasions."So the text messages suggest that he was arranging to go to Sam's that day."The episode, which aired on Thursday, July 30, examines how investigators used digital evidence to build the case against Watson after he fled the UK following the killing.‌Ms Holden, a sex worker, died at her home on September 9, 2022. After murdering her, Watson travelled to Belgium, where he was arrested at a hotel two days later before being extradited to the UK.The court heard Ms Holden's body was discovered by her 18-year-old son shortly after 4pm. She was lying on the floor, covered with a blue dressing gown, and was pronounced dead at the scene. Watson's DNA was later found on her neck and beneath her fingernails.‌During his trial, jurors heard Watson had first contacted Ms Holden through an adult website in May 2022, where she advertised under the name "English blonde lady". The pair had met several times before, leading the judge to conclude Ms Holden trusted him.After the killing, Watson disposed of Ms Holden's phone at St Pancras station before boarding a Eurostar train bound for Belgium.At Winchester Crown Court in 2024, Watson, then 37, was handed a life sentence with a minimum term of 21 years.Article continues belowIn a heartbreaking victim impact statement, Ms Holden's daughter, Rebecca Elliott, described her mother as her "best friend, my soul mate and most importantly my mum".The court also heard during sentencing that Watson had a violent criminal history. He was on extended licence after serving a sentence for sexually assaulting another woman in 2013, having admitted the offence. The court was also told he had previously been charged with wounding members of his own family in 2008.Episode three of Murder Case: The Digital Detectives is available to watch on Channel 4 now