Between the air raids they made physical sacrifices so their loved ones would be able to eat.

Second World War film Operation OMO may make you think of the battlefront but this story, set in Medway, portrays the lesser known tales from the Home Front and women’s own ‘washing powder war’.

The film follows women like Winifred and Lily who – at the sight of their thin children – feel pressured into borderline prostitution with the grocer for a few extra chops and vegetables.

Then young GI Caleb arrives, laden with all-American charm, chocolate and Coca-Cola – and the sexual politics of cheating is made even more complicated.

The movie is filmed in Rochester and Chatham and writer/director Sonya Roseman invited me down as an extra for the day.

Hair in victory rolls, lacquered firmly into place, and dressed in 1940s clothes, I was in my element and remain utterly convinced that I was born in the wrong era.

My role involved a few disgusted looks and an indignant “what! Americans...” when I discover the Yankee I’m on a date with has another lover.

Sonya, 34, is half way through filming but still welcoming other extras to the set. The actress of The Fairway, Rochester, said: “I’m doing this partly to help local people and hope it does something for all of us. I wish I’d had an opportunity to be a part of a film like this when I left university.

“My heart is in this and I’ve got a good feeling about it.” Sonya studied drama and film in Canterbury and added: “In an ideal world we’d have a big production company and a historian working on this with us, but I have no budget and what I’ve done I’ve built from my own research.”

Sonya is joined by producer and editor Colin Marrison for the filming.

The film’s title comes from the notorious tradition of married women putting OMO packets on display at their windows to signify to their lovers Old Man Out.

Sonya scripted the story after success with her First World War film Never To Be Parted which has been nominated for a Special Achievement Award with the Golden Poppy Awards.