I felt sick as we climbed back topside, the captain explaining that we weren't to talk about this, not to anyone. It was all top secret. In other words, a cover-up was in force. We were to forget the girl, forget the homing device - none of it had ever happened. But I couldn't get the image of her spread-eagled against that bulkhead out of my mind.

Tom and Doug were waiting on deck. The ops officer told us to get our kit together before our regimental helicopter flew us back to rejoin the unit.

That was when all hell broke loose.