Colin Coats and Philip Wade inflicted the most cruel and horrific catalogue of violence on Lynda Spence in her last days.
They hurt her over and over, smashing her knee caps with a golf club, chopping off her thumb, crushing her toes and burning her hands with an iron so badly that it left marks from the steam holes.
Ms Spence, 27, suffered the added humiliation of sitting in her own waste for at least 13 days, having been taped to a leather chair with just a tin under it to collect the mess.
She was forced into a car in Glasgow on 14 April, 2011, and driven to what would be her slow, painful death in a quiet residential street in West Kilbride, Ayrshire, where she was held captive.
Coats’s motive was financial. He lost tens of thousands of pounds in a deal apparently dreamed up by Ms Spence, involving a land development next to Stansted Airport.
After being strung along by Ms Spence for the best part of a year, Coats’s greed got the better of him. He lost face in the lie, along with all of his money, and he snapped, deciding upon a revenge attack that would bestow the most callous punishment.
He was in command, with Philip Wade as his right-hand man. Wade worked with Coats every step of the way, from Ms Spence’s abduction in Broomhill Path to disposing of her body.
As she sat in that chair for the last two weeks of her life, Ms Spence never once called out for help. At one point she did ask David Parker and Paul Smith, who were offered money to guard her, if they thought Coats and Wade would ever let her go.
Ms Spence also spoke of feeling better after talking to her parents briefly during the ordeal, taking comfort in hearing their voices again.
Coats and Wade are believed to have decapitated the businesswoman and disposed of her remains. The question of where her body ended up is still unanswered.
Coats and Wade also threatened potential witnesses, many of whom told the court that they were terrified and disgusted by what they learned.
Coats came up with a story to suit the circumstances of Ms Spence’s mysterious disappearance, saying he helped his “close friend” when she needed to get out of Glasgow because she was being threatened and extorted by other business associates.
Forensic experts could only find one spot of blood at the Meadowfoot Road flat which matched Ms Spence’s DNA profile.
It was discovered on the bathroom floor, obviously missed as the men mopped up the rest of the mess.
Apart from this one physical clue, the Crown’s case rested on circumstantial evidence.