We closed on the cubicle as a pair, and the short, sandy-haired guy in occupation was so riveted by her cleavage that he scarely got his eyes on our documents or on me. In a couple of seconds we were through and waltzing through the Customs hall. Glancing back, I saw Whinger in another of the queues, still on the wrong side of the barrier.

As soon as we were clear, I said, ‘Thanks. Where would you like him taken?’

‘We’re on the train.’

‘OK. This way.’

When I sneaked another glance behind me I saw that Whinger had been rumbled: the man on the desk had stopped him, poor bugger, and called in a superior.

We started walking again and I said, ‘Where are you going?’

‘London. Don’t tell me – you’re coming as well?’

‘Wish I was. No – I’m driving. But I’m not in any hurry. I’ll see you on board.’

In the terminal a train was already standing at the platform, so I did as I’d promised and sat the child down and waved goodbye, not without a touch of regret. Lemon Jane could have been a lot of fun.

Then, as I stepped back on to the platform, I was jerked out of my reverie by the sight of a stocky, fair-haired young guy walking past. There was something familiar about his shape and gait – a bit of a roll in his walk – but at first I didn’t recognise him. Then suddenly I saw that it was Rick Ellis, one of our team, wearing a blond wig. I almost called out to him but stopped myself just in time: it was still conceivable that someone was tailing him, and I didn’t want either of us compromised.

Crafty sod! His disguise had carried him clean past Immigration, and it looked like he was away.

I knew that anyone captured would be taken to the Intelligence Corps headquarters at Ashford, which was running the exercise, so I dug my mobile phone out of my pack and called the Ops Room. After being passed around for a bit I heard a familiar Scottish voice – Jock Morrison, the Assistant Int Officer from Hereford, who was monitoring the interrogations.

‘How are we doing?’ I asked.

‘They’ve got two of your guys here already, and they reckon they’ve just picked up a third at Folkestone.’

Whinger, I thought. But all I said was, ‘OK – I’m through, and I’m coming in.’

I knew the lads would have been taken across in blacked-out vans so that they wouldn’t know where they were, and although they wouldn’t get physically knocked about, they would have a hard time of it all the same, being deprived of food and sleep, and repeatedly brought back for re-interrogation throughout the night.

Having hired a Golf from the Avis desk in the terminal, I shot up the M20 and reached Ashford in under half a hour.