‘We’ll tell the press seven,’ Catherine said, eliciting a wry smile from Zoe. ‘This wasn’t a one-off, either. Looks like they were using the left-luggage facility as an escrow holding point. It’s a way of doing a large-scale drug deal without the risk of anybody getting fingered handing over or receiving the merchandise. We’re guessing the wholesaler leaves the shipment there and then supplies the locker number and combination to the buyer once payment has been received.’

‘Got you,’ Zoe said. ‘So then the buyer pitches up and walks away with the suitcase without either party having to be in the same room at any point. Vendor could get off a train from London or wherever, make the drop, then get the next train back again, minimum exposure.’

‘Depending on what stage of the transaction had been reached, this could get very messy. There’s bound to be quite a “he said, she said” between the wholesaler and the buyer over who owes who.’

‘“Likely to prove explosive”,’ Zoe quoted, opening up another interpretation of the informant’s carefully chosen words. ‘Any word on who the buyer was likely to be?’

Catherine thought of Frankie Callahan’s distracted calm, his controlled management of her visit, a man not wanting any complications; a man with something major in the offing.

She could see Laura through the glass, striding towards Catherine’s office with that serious, determined look on her face. It was good to have someone working alongside you with that level of application and commitment to the job in hand, but if the lassie didn’t lighten up a wee bit now and again, she was going to start worrying.

Laura had spent most of the previous day diligently probing for holes in Gary Fleeting’s alibi, going at the task like it was her predestined purpose in life. The guy had baited and patronised her with what he believed at the time to be impunity. Instead he had just made it Laura’s sole ambition to put him away.

Laura tracked down the one-night stand, a girl called Lyndsay McLaughlin. She admitted sleeping with Fleeting, but it was the sleeping part that was a problem for his alibi. Lyndsay said she woke around two in the afternoon, so couldn’t confirm Fleeting’s claim not to have left until after one.

The Bay Tree was starting to show gaps in its foliage too, as far as it covered Fleeting’s evening. All the diners Laura spoke to confirmed that they had seen him working behind the bar, but they were less certain about whether he was still there around the time they were leaving. One did say he was fairly sure Fleeting served him during last orders, but admitted to having had quite a few by that point. Pissed revellers did not play well in court as witnesses, no matter what they did for a living or how posh their postcode.