Stacey bit into it and experienced the oddest emotion. Sure, the muffin tasted nice, but it wasn’t that. It was the fact that the cake was home-made. It struck her that no one had ever baked her a cake, made something just for her. How sad that was.

‘You don’t like it, do you?’ Jay said.

She swallowed, unable to speak for the lump in her throat. It wasn’t the muffin. ‘It’s the nicest thing I’ve ever tasted.’

He gave her a pleased smile. ‘I’ll tell Ravinder. She’ll be really happy to hear that.’

‘Her children are very lucky to have her,’ she said rather shakily.

‘We are, aren’t we? Next time I’ll make sure she adds another muffin to my lunch box. Now. Ratty. We’ve checked his home, his usual haunts, and we’ve spoken to the few people he hangs around with. Where next?’

Stacey licked the last of the crumbs from her fingertips. ‘I think I know where his mother lives. He might be there. She’s in the static caravan park at Teasel Woods, and be warned, she’s mad as a box of frogs.’

Twenty minutes later they pulled up by the site manager’s office. The tatty statics at Teasel Woods had all seen better days. A while back, the place had been at the centre of a drug investigation. The gang that ran it had all been apprehended, and since then the park had been virtually deserted.

‘You do bring me to the nicest places,’ said Jay, stepping over a wide muddy puddle. ‘And considering we’ve had no rain, where has all this water come from?’

Stacey chuckled. ‘I don’t think you want to know.’

‘Some holiday camp — who stays here anyway?’ Jay wrinkled his nose. ‘It’s not going to feature in any tourist brochures, is it?’

‘It’s a dump, little more than a gypsy camp really. The people here are just one step up from homeless. Some are transient seasonal field workers, some can’t afford a proper home. Some just finished up here and never left, like old Ma Jones.’

‘Ratty’s mother?’

‘Yes — and a word of warning, never call him Ratty to her face, okay? I’ve seen her deck someone for that. His name is Reginald.’

‘Got it.’

Stacey stopped outside a small, old-fashioned caravan with frilly net curtains at the windows. Thirty years ago it might have looked pretty, but the curtains were unwashed, the paintwork peeling. She knocked on the door, then stood back. Ma Jones didn’t appreciate visits from strangers.

‘Mrs Jones? Can you spare a minute?’

After a while, the door cracked open just wide enough for them to see an elderly woman peering through the narrow gap. She was tiny, extremely thin, and her grey hair stuck out in all directions. Her eyes were small, colourless, disconcertingly piercing and suspicious. ‘What do you want?’

‘Hello, Mrs Jones. We were wondering if Reginald is staying with you at the moment. We need to have a word with him.’

‘Oh, it’s the filth, is it? Well, sod off, he ain’t ’ere!’