It was an El Alamein reunion in the Albert Hall. Monty was in his box. Vera Lynn and Marlene Dietrich were the stars.

Vera Lynn was on stage alone, singing. I was watching from the wings. So was Marlene Dietrich, standing as close to the stage as possible without being seen by the audience. She was wearing jodhpurs and carrying a riding whip. She was slapping her breeches in time with the music. It was a short, sharp, stinging slap. If I were a horse I would have looked lively.

Vera was wearing a short, full-skirted dress that floated around her like a flower. She leaned forward gently as if singing to one man. She assured him that they would meet again though she seemed vague on the details. Very much the girl in the soldier’s wallet.

When Marlene went on in a solo spotlight she was wearing sprayed-on silver glitter. She looked like a cobra who had dined lightly but deliciously. I was transfixed, wondering, for one thing, how anyone could get out of those skin-tight jodhpurs and into that skin-tight glitter in the time available. She sang in heartbroken throaty tones that she was waiting underneath the lamplight by the barrack gate. Definitely not the girl next door.

Well, it takes all sorts to keep our lads cheerful.

But ... that image has stayed with me for more than half a century because I don’t quite understand it. Marlene Dietrich listening so intently to Vera Lynn and whipping herself.