Graham Tulloch
Drystone Lane, Nether Haddon, Gloucestershire, Cotswolds — autumn 2025
Case File Sealed
The solution to WW-2026-001 is classified. Opening this file is irreversible.
The Solution
The Killer: Caitlin Howell
Relationship: Personal assistant for four years. Daughter of Tulloch's late business partner, Derek Howell, who died in 2020.
Motive: Caitlin discovered proof in Tulloch's personal files that he deliberately defrauded her father out of his share of Tulloch-Howell Properties before dissolving the company. Her father died of a heart attack in 2020, which Caitlin attributes to the financial stress. She has been planning the murder since finding the documents eight months ago.
Method: Caitlin drove her silver Volkswagen Polo along Drystone Lane at approximately 6:20 p.m. on Friday 14th November, knowing Tulloch walked the lane every Friday evening between 6:00 and 7:00 p.m. She accelerated into him at the blind bend, struck him, and continued without stopping. She then drove to a car wash in Stow-on-the-Wold (15 minutes away) at 6:48 p.m. to clean any evidence from the vehicle, and returned home to Cheltenham.
Opportunity: Caitlin knew Tulloch's walking routine intimately, having worked as his PA for four years. She left the village on Friday afternoon ostensibly to drive home to Cheltenham but instead waited on a farm track off the B4068 until 6:15 p.m. before driving north along Drystone Lane. The lane is unlit and has no CCTV.
Chain of Evidence
- Step 1: The paint fragments on the victim's clothing are silver metallic Volkswagen paint (colour code LA7W, Reflex Silver). This does not match Poole's Land Rover (green over white) or Farrow's BMW (dark grey). Caitlin Howell drives a silver Volkswagen Polo.
- Step 2: Caitlin's witness statement says she saw Tulloch's porch light on at 'about half five' as she drove past on her way home. But the smart home system log shows the porch light activates on a timer at 6:00 p.m. At 5:30 p.m. the light was not on. She could only have seen it if she drove past after 6:00 p.m., placing her in the village during the murder window.
- Step 3: A car wash receipt places Caitlin at the Cotswold Car Wash in Stow-on-the-Wold at 6:48 p.m., 28 minutes after the estimated time of impact. Stow is 15 minutes south of Drystone Lane. She was cleaning the vehicle that struck Tulloch.
Red Herrings Explained
Damage to Marcus Poole's Land Rover bumper
He reversed into the pub's gate post on Wednesday. The postman, Ray Gerrard, witnessed this and confirmed it. The paint transfer on the bumper is green, matching the gate post, not consistent with a pedestrian impact.
Poole's comment at the parish council: 'Someone ought to run that man off the road'
Pub landlord bluster at a public meeting about a planning dispute. The kind of thing said in frustration, not the language of someone planning a murder.
Diane Farrow's threatening text messages to Tulloch
She was pursuing the hidden assets through a solicitor and the courts. Her threat to 'make him pay' was about the legal claim, not physical violence. Her alibi is confirmed by phone location data and a Ring doorbell camera.
Diane Farrow's dark-coloured car and presence in the village
Her BMW was parked in Sophie's drive from 4:10 p.m. Friday to 9:45 a.m. Saturday, confirmed by a neighbour's doorbell camera. The paint on the victim's clothing is silver, not dark grey.
The Solution: Case WW-2026-001
Drystone Lane, Nether Haddon, 14th November 2025
Every Friday evening at six o'clock, Graham Tulloch put on his waxed jacket and flat cap, took his walking stick from the stand by the door, and walked south along Drystone Lane. Eight hundred metres to the B4068 and back. The same route, the same time, for years. Marcus Poole saw him pass the pub. The village set its clocks by him.
On 14th November, someone used that routine to kill him.
The vehicle came from the south, travelling north along the lane towards the village. It accelerated into the blind bend at 40 to 50 mph. It struck Tulloch squarely, throwing him into the drainage ditch. It did not stop. It did not brake. The tyre marks on the road surface show only acceleration.
Let us consider who did not drive that vehicle.
Marcus Poole had the loudest motive and the most visible evidence against him. He had publicly told a room full of people that "someone ought to run that man off the road." His Land Rover had a dented bumper. He admitted to stepping outside the pub at 6:15 p.m., right in the middle of the window.
But the bumper damage is from reversing into the pub's gate post on Wednesday. The postman witnessed the collision. The paint transfer on the bumper is green, from the gate post, not silver. More to the point, the paint fragments on Tulloch's clothing are Volkswagen Reflex Silver, colour code LA7W. Poole's Land Rover is white. And the tyre marks at the scene are from 185/65 R15 tyres, the kind fitted to small hatchbacks. A Land Rover Defender uses tyres nearly twice that width. Poole's vehicle was not involved.
His cigarette break lasted eight minutes. Two regulars saw him return to the bar at 6:23 p.m. The blind bend is 280 metres from the pub. To drive there, commit the act, and return, he would have needed to walk to the car park, start the vehicle, drive to the bend, return, park, and walk back, all in eight minutes, without anyone in the pub hearing the engine or noticing his absence. It does not work.
Diane Farrow had the bitterest grievance. Eighteen years of marriage, a contested divorce, and £300,000 in hidden assets. She sent a text threatening to make Tulloch pay. She was in the village that evening. She drives a dark-coloured car.
But her BMW never moved. The Ring doorbell camera at 3 Church Lane, directly opposite her daughter's cottage, recorded the BMW in Sophie's driveway from 4:10 p.m. on Friday to 9:45 a.m. on Saturday. Her phone placed her at the cottage continuously. Her car is dark grey, not silver, and the paint on the victim does not match. Diane's anger was real but she was pursuing Tulloch through the courts. She needed him alive to face the claim.
Which leaves Caitlin Howell.
The Evidence Chain
Step 1: The paint. The fragments embedded in Tulloch's jacket and trousers are Volkswagen Reflex Silver Metallic, colour code LA7W. This does not match Poole's white Land Rover or Farrow's grey BMW. Caitlin Howell drives a 2019 Volkswagen Polo in Reflex Silver. Her vehicle's tyres are 185/65 R15, matching the tread marks at the scene. The forensic examination of her car found a hairline crack in the nearside fog lamp surround with a fibre caught in it, and evidence of recent commercial jet washing.
Step 2: The porch light. In her witness statement, Caitlin says: "As I drove past the house, I could see his porch light was on. It must have been about half five." But the smart home system log, confirmed by CSI Payne, shows the porch light is on a daily timer set to activate at 6:00 p.m. It has been set to this time since the system was installed in April 2023. At half past five on 14th November, the porch light was not on. Caitlin could only have seen it illuminated if she drove past The Old Rectory after 6:00 p.m. She was not leaving at half five. She was still in the village.
Step 3: The car wash. A receipt from the Cotswold Car Wash in Stow-on-the-Wold is timestamped 6:48 p.m. on 14th November. Payment by contactless card ending 4471, registered to C. Howell. Stow-on-the-Wold is approximately 15 minutes south of Drystone Lane via the B4068. If Caitlin struck Tulloch at approximately 6:20 p.m. and drove south, she would have reached the car wash at almost exactly the time the receipt shows. She was cleaning the evidence from her car.
Red Herrings Explained
Poole's bumper damage: From reversing into the pub's green-painted gate post on Wednesday. Witnessed by the postman. Green paint transfer on the bumper, not silver. The Land Rover's tyre size does not match the scene.
Poole's public threat: Bluster at a parish council meeting, spoken in frustration in front of twelve witnesses. The language of a man venting about a planning dispute, not the careful planning of a premeditated killing.
Farrow's threatening texts: She was pursuing the hidden assets through a solicitor. "Make him pay" meant through the courts. Her alibi is confirmed by phone data, her daughter, and a Ring doorbell camera that recorded her car stationary all evening.
Farrow's dark car and presence in the village: The paint on the victim is silver, not dark grey. The BMW did not move. Diane walked to the shop at 5:28 p.m. and returned at 5:41 p.m. She did not go near Drystone Lane.
The Key Inconsistency
"As I drove past the house, I could see his porch light was on. It must have been about half five."
Caitlin Howell's statement is the warmest, the saddest, and the most sympathetic of the three. She speaks of Tulloch with genuine affection. She describes her father's death without bitterness. She presents herself as a loyal assistant who was given a lifeline by a generous man. It is the kind of account that makes you want to look elsewhere for the killer.
But the porch light gives her away. The Hive smart home log is unambiguous: the light comes on at 6:00 p.m. every day, on a timer that has not been changed since 2023. At 5:30 p.m. in November, it is dark outside, which is why the detail feels plausible. It should have been dark enough for a porch light. But the light was not yet on.
Caitlin said "about half five" because she needed to have left the village before Tulloch set out on his walk at 6:05 p.m. If she was seen or placed in the village after six, she would have no explanation for being on Drystone Lane. So she moved her departure earlier. The porch light was a detail intended to anchor the time, to make the statement feel grounded and specific. Instead it proves she was lying.
She did drive past the house, and the porch light was on. But it was after six o'clock, not before. She saw the light because she had waited for it to come on, waited for Tulloch to leave, and then driven south to the B4068 before looping back up Drystone Lane to meet him at the bend.
Her phone was off from 5:35 p.m. to 7:20 p.m. Not a dead battery. A deliberate gap. Caitlin Howell knew exactly what she was doing and for how long she needed to be invisible.
Historical Note
Vehicular homicide staged as a road accident is one of the most difficult crimes to prosecute. In rural areas without CCTV or witnesses, the default assumption is always tragic accident: a pedestrian in dark clothing, an unlit lane, a driver who did not see them. Investigators must prove intent, which means proving the driver knew the victim would be there, chose to accelerate rather than brake, and took steps to conceal the evidence afterwards. The regularity of a victim's routine, which makes them vulnerable to such an attack, is also what makes the attack provable: if the killer knew the routine, they can be connected to the knowledge. In cases where the killer and victim are closely associated, the very intimacy that provided the opportunity also provides the trail.
Case WW-2026-001. The killer is Caitlin Howell.