She dealt with it in a matter of minutes – unplugging the toaster and smothering the flames with a fire blanket then, when it was cool enough to touch, she wrapped it in a tea towel and deposited it in the skip in the car park. When she returned, the stench of burnt toast hit her even before she opened the front door, and when she stepped into the house she discovered the guests, crowded together in the kitchen, arguing about who put breakfast muffins in the toaster when they were told on the first day that the toaster slots were too small for anything larger than a slice of bread. Kate had sailed past them, down the corridor and out the back door.

Now, she steels herself. She’s going to have to go back in.

As she makes her way down the corridor she hears classical music coming from one of the bedrooms. She pauses beside Geraldine’s open door. She was told not to play music without headphones, as were all of the guests. Does no one listen to a word she says? Sighing, she snatches up the source of the noise, a mobile phone, lying on the carpet. It’s ringing, rather than playing music, and she’s just about to hit the red ‘end call’ icon when something prompts her to hit green instead.

‘Hello?’ She holds it to her ear.

‘Is this Fran Fitzgerald?’

Her first instinct is to reply ‘No,’ but she catches herself. ‘Yes,’ she says tightly. ‘Who is this?’

Even as the words leave her mouth she’s running the name Fran Fitzgerald through her brain.

‘This is DS Marchant,’ says the voice in her ear. ‘I’m following up on a sexual assault that took place on the London Underground last year. I understand you witnessed—’

Kate jabs at the ‘end call’ button and stares at the phone in her hand, breathing shallowly. Fran Fitzgerald. That’s what the DS said. Why is that name familiar? Fran … Fran …

She stares around, searching the walls, the corners, the bed, the carpet, as though the answer lies somewhere in the fixture and fittings of the bland, beige room. Fitzgerald? She squeezes her eyes tightly shut. She knows someone with that name. Who? Who?

Jenna. Her eyes fly open. Jenna’s last name was Fitzgerald and she’d mentioned a sister called Fran in one of her sessions. That explains it – why Geraldine mentioned Jenna in the first group meeting, why she’s been sneaking around with Caroline, why she regularly gives Kate dirty looks.

Geraldine Rotheram is Fran Fitzgerald, and she’s helping Caroline with her story.

She needs to talk to her, to try and unpick the damage Caroline has done. She needs to—

‘Oh!’ She gasps in surprise as she steps into the corridor. Tom is two feet away, his eyes dark, his expression unreadable.

‘Oh my god, Tom,’ she says. ‘You’ll never guess what I’ve found out.’