‘Assuming his papers are in order and he didn’t attempt to purchase his ticket with Reichsmarks, he oughtn’t to have had any problem. I presume they’ve sent over someone who speaks decent English. Likewise on the King’s Cross train. We rely on the railway staff to be alert. I assume there’s no description of him, nothing like that?’

‘Of course not. You’d better get to Mablethorpe tonight, Prince. Be ready to start looking for this chap first thing in the morning.’

Prince looked at the Chief Constable, hoping he’d say something. The Chief Constable glanced away.

‘I’d prefer to go first thing in the morning, sir. One or two things I need to sort out first. How will I contact you?’

‘You don’t need to worry about that. I’ll be joining you.’

‘I need to have a word with you.’

Prince had left, and the Chief Constable followed the Scotsman into the corridor outside his office. The windows were draped in blackout material and the only lighting came from a couple of weak bulbs high above, casting a yellow gloom over them.

‘It’s about Prince. I hope you don’t think he was being rude just now. You know… telling you he’s not going to Mablethorpe tonight.’

‘I did wonder.’

‘There are… reasons.’ The Chief Constable sounded awkward. ‘Two years ago, his wife and daughter were killed in a motor accident, just outside Lincoln. She was turning out of a minor road onto the main road and they went smack into an army lorry – didn’t stand a chance. His daughter was only eight. Tragic, of course, and for reasons I’ve not quite fathomed, Prince blames himself. I suppose that’s what you do… blame yourself.’

‘How dreadful.’

‘Indeed. His son, Henry, was supposed to have been on the outing with his mother and sister but stayed at home with a nanny as he was unwell. He’s a smart little chap; Prince brings him in here every so often. He was just a year old when the accident happened. Prince is absolutely devoted to him. They have a nanny and a housekeeper, but Prince is wonderful, doing the kind of things for the boy you wouldn’t imagine a father doing: he takes him for walks and even gives him baths, I’m told. He likes, if at all possible, to be there when Henry goes to bed and when he wakes up in the morning. He’s such a smart detective I’m happy to cut him a bit of slack. I simply thought you ought to be aware, though he wouldn’t expect any special treatment. If this German chappie is in that area, Prince is by far your best chance of finding him.’