Kevin, who plays wartime field hospital commander Lieutenant-Colonel Roland Brett (pictured) in the new series, gives the OU a glowing endorsement in an interview on the BBC website.
Apart from providing the historical context for his role, his study gave him something useful to do while hanging around on set waiting to be called, he says.
"I’d recommend it to absolutely anybody. It’s a wonderful way of learning."
The Crimson Field, a six-part series written and produced by Sarah Phelps, aims to present one of World War One's untold stories – the work of doctors, nurses and female volunteers treating men wounded in the trenches in tented field hospitals behind the Front Line.
- The first episode aired on Sunday 6 April, 2014 on BBC One.
- See more about the OU/BBC First World War co-production Britain's Great War