As Ben had guessed, the van was parked in one bay of a domestic block-built double garage, the other half filled with garden tools and shelving units and all the utilitarian clutter of the typical middle-class suburban home. Colonel Monty’s pistol was no longer in evidence, and his manner was courteous and apologetic. ‘I do hope you can forgive me for all these precautionary measures. Your telephone call did leave me in something of a quandary. No hard feelings?’

Ben replied, ‘None at all, Colonel.’ Grace said nothing, obviously not quite yet ready to forgive him.

‘Your car keys,’ Monty said, returning the Mercedes fob to Ben. He hung his coat on a peg and removed the broad-brimmed hat, revealing a wispy comb-over of white hair. Then he ushered them through the garage to an interior door that led inside his home. The house was large and tastefully furnished, if a little on the formal side, as suited a retired military officer of Monty’s generation. One wall proudly displayed a whole montage of framed photographs, the older ones in black and white, dating back through the colonel’s career to his early days at Sandhurst. The stooped, crooked Monty of today was a far cry from the dashing, ramrod-straight figure of a man he’d been in his glory years.

‘Please, make yourselves comfortable,’ the colonel said, showing them through to a sizeable conservatory filled with chintzy woven rattan armchairs and sofas. Icy rain pattered on the windows and glass ceiling, but the room was warm and inviting. As they entered, a corpulent grey-haired woman whom Ben presumed to be Mrs Montgomery appeared in the doorway. She was dressed as though getting ready for bed, in dressing gown and fluffy slippers.

‘This is my wife, Eunice,’ Monty said. Ben introduced himself and Grace. Eunice was all smiles, as though greeting old friends. ‘Grace, that’s such a lovely name. You must be hungry after your long journey, dear. Would you like a piece of apple tart?’

‘That’s very kind of you, perhaps just a small slice,’ Grace said, making an effort to be polite.

Eunice beamed with joy. ‘That’s wonderful. I’ll just go and bake one.’ She hurried off towards the kitchen, dressing gown swishing around her.

And folks said Monty was mad.

‘Will you take a drink?’ the colonel asked, opening a cabinet that housed a row of bottles and glasses. Ben asked for scotch, neat. Grace declined. Monty took out a pair of crystal tumblers and a bottle of good single malt, set them down on a glass-topped table and poured out two enormous measures that would have befitted a hard-drinking officers’ mess of old. The colonel settled on a rattan armchair. Ben took a seat on one of the matching sofas, and Grace sat next to him.