Grace wasn’t alone. With her was a sandy-haired woman of about the same age, dressed in civvies, either a plain-clothes officer or a civilian admin staffer. Grace was still wearing most of her uniform but could have passed for a regular citizen, in the same raincoat and cap she’d left home with. Jeff took the binoculars from Tuesday and tracked her as she and her companion trotted down the steps from the building and crossed the car park towards her Land Rover. The breeze off the hills made Grace’s black hair stream out from under her cap. The two women were laughing as though sharing a joke.

‘She really has no idea she’s being followed, does she?’ Jeff commented.

Tuesday asked, ‘Where are they going?’

‘Lunch break, maybe.’

‘They don’t have a staff canteen?’

‘Have you ever eaten in a cop shop canteen?’ Jeff asked. ‘I have.’

‘Bad?’

‘You don’t want to know.’

Grace and her sandy-haired friend got in the Landy and it pulled out of its parking space with a puff of smoke. As it neared the gates the black Range Rover came to life and followed. Jeff started up the Transit. ‘Show time.’

Grace turned left onto the bypass. The Range Rover shadowed her at a discreet distance. Jeff hung back, keeping about twenty car lengths between himself and the watchers. There was little other traffic. At the end of the road Grace took another left off a roundabout and headed towards town. Her driving style was relaxed and casual. After about quarter of a mile she turned into another car park, this one belonging to an edge-of-town pub called the Thistle.

It was now 12.34 p.m. and the place seemed to be doing a roaring lunchtime trade. Grace slotted into one of the few remaining spaces and she and her friend got out just as the black Range Rover rolled into the car park. They didn’t so much as glance at it. Jeff passed by the Thistle and halted fifty yards down the street, within sight of the entrance. They watched as Grace and her friend entered the crowded pub. The watchers stayed put inside their car.

Tuesday said, ‘Now what? We’re still no closer to her than before, with those guys sticking to her like a magnet. Soon as she’s finished lunch she’ll go back to work and we’ll be back where we started.’

‘I’ve had an idea,’ Jeff replied with a twinkle in his eye.

‘Which is?’

‘Wait. Let them get settled in first.’

Tuesday scowled. ‘I have no problem with waiting, as long as I know what the hell I’m waiting for.’

‘Chill out. You’ll see. We might have caught a break here.’

Exactly four minutes after Grace and her friend had vanished inside the pub, at 12.38 p.m., Jeff took out his burner phone.