But Rhiannon saw her. Rhiannon knew exactly what was going on. And before Hilary or anyone else could stop her, she was gone, pushing through the tourists, buffering people out of the way, listening out for Ty’s cries, keeping a fixed view of the blonde head as it got further and further away.

I desperately kept my eyes on the pilfering prize. The woman was so fast, and a few hours on a treadmill for the first time in fifteen years wasn’t cutting much ice when it came to stamina. But somehow my body responded, flooding me with the adrenaline I needed and pumping it furiously into my limbs. As the tourists thinned out and the streets narrowed, the woman slowed to a jog up a cobbled street, away from the shops, encumbered by her heavy screaming cargo.

She thought she was home and dry. My feet were light. I grew closer. She got slower. She had her hand over his mouth but he was wriggling violently. She hit him across the face. Shouted in Italian to shut him up.

My breathing was fast. She didn’t hear me coming.

I reached out and grabbed her blonde hair hard in my hand and yanked her backwards, forcing two fingers into her eyes.

‘DROP HIM NOW.’

She dropped Ty instantly – I could hear him crying but it was like the sound was underwater. All I could concentrate on was her and inflicting as much pain as I could.

She wriggled and jiggled in my arms and screamed and bit down on my skin as I thrust my arm tight into her neck and pressed down.

Ryan was there, scooping a bellowing Ty into his safe arms, sweating and puffing.

‘Oh my God, oh my fucking God,’ he cried. ‘I thought we’d lost you.’ He cuddled that little boy so tightly. A true dad.

But I was having a party. The blonde woman’s knees buckled as she sank to the ground, the tighter my arm became around her throat. When she was weakened, I thrust her forwards to the cobbles and pulled her round to face me. I mounted her. Nothing was going to stop me now. Nothing could.

It was back – that molten feeling. That urge. The wetness between my thighs as I strangled her. This potential paedophile who’d stolen my best friend. The rippling, crippling can’t-do-anything-else-but-kill thrill sizzled all the way through me. Oh, how I wanted her. So badly. Just like Derek. Like Sandra. Like Troy and Gavin and Daniel and those men at the quarry.

This was fucking paradise.

I straddled her body and smashed her head back onto those cobbles, again and again. And I whispered in her ear: ‘You die now. You fucking die now.’