Strange. It rang straight through to her answer phone. I waited five minutes and tried again, this time leaving a message wishing her a happy Christmas, and enquiring as to whether she was all right, given that she hadn’t answered the phone.

‘She could be in the garden, filling up her bird feeders,’ I speculated, worry tugging at my gut. ‘Or in the shower.’

‘Asleep?’ Henry suggested.

‘At eleven in the morning? If it was the afternoon, possibly, but not at this time.’

‘She could have gone for a walk.’

I shook my head. ‘She can barely manage the garden path on a good day. There’s no way she’d have gone out in the snow.’

‘Where does she live?’

‘Newark. Not too far from the castle.’

‘Do you have the address?’

‘No. Why?’

‘If she’s still not answering when we reach the turn-off from the A1, I’ll keep on going and we can check in on her.’

‘Henry, that’s miles out of our way…’

He kept his eyes on the road, face impassive. ‘An extra forty minutes, tops. If the roads remain this clear we’ll still be back in time.’

‘Not if we find her lying on the floor with a broken hip. Or in bed with the flu.’

Henry waited until he’d overtaken a lorry before replying. ‘So, on the basis she might be stuck on the floor or ill, you don’t want—’

‘Okay! Yes. If we can find out her address then maybe we can drop by. If you’re really sure.’

‘I’m really sure that if we don’t, you’ll spend the rest of the day worrying about her.’

With a bit of online searching, I had an address for Muriel Lewinski. A mile before we reached the turn-off towards home, I called again. No answer. A prickle of anxiety skittered up my spine. Dad messaged to ask if we had an ETA. I blew out a shaky sigh and told him an hour.

Twenty minutes later, we pulled up outside a shabby terraced house on a narrow street. It was nearly one o’clock. I knocked on the front door with a clammy fist, Henry standing right beside me.

After a few minutes of knocking and waiting, we found a passageway that cut through the terrace a few doors down. This then required us to climb over a gate stuck shut due to a rusted bolt so we could hurry up to the back door, Henry peering through the kitchen window while I knocked again.

‘Can I help you?’ a suspicious voice carried over the next-door fence.

‘Hi,’ I blurted, jumping back from the door as though confirming their suspicions.

A youngish man was scowling at me, the trail of a cigarette drifting above his head.

‘All right, Dale?’ A woman who looked to be his mum appeared next to him.

‘These people are poking around Mrs L’s house.’