SAS Rogue Heroes is back on BBC One and in the series, Lt John Tonkin (played by Jack Barton) is captured during the fighting in Termoli. Hitler had issued a Commando Order, which meant any captured commando should be executed.

The episode sees Tonkin being led outside where a firing squad is waiting for him, but he is saved at the last minute by a sympathetic German officer. While this element was added for dramatic effect, there are many parts of Tonkin's escape that are true.

The hero was captured when his unit found themselves amongst the German army, but German officer General Heidrich invited him for a dinner to discuss the brilliance work of the SAS.

Heidrich was a veteran of the First World War and having been a parachutist himself, he enjoyed sharing stories with captured paratroopers. In the series, Heidrich warned Tonkin about the Commando Order and how he wouldn't survive the next day.

In real life, it was actually a German major who had warned him after he was driven back to his cell following dinner. He told Tonkin he would be handed over to the special police.

Tonkin was told: "From now on the German army cannot guarantee your life."

While the series sees Tonkin take on three Germans in a bid to escape, the real Tonkin's escape was nowhere near as dramatic.

He was able to sneak out of a jeep before wandering around for two weeks, when he came across a British patrol and was reunited with the newly named SRS.

Cambridge University's website has an Obituaries page which features some interesting insight about Tonkin's capture and subsequent escape.

It said: "He landed with his squadron at Termoli on the Italian mainland and was captured.

"On the night of his capture, he dined, as a fellow parachutist, with a general who advised him, in veiled language, to escape, since, as a commando, he was to be sent to Germany for execution.

"Tonkin took the advice, escaped from a truck, and walked half the length of Italy to rejoin his unit, only to find he had been reported as missing and, as was the custom, all his effects had been auctioned and the money sent to his 'next of kin' together with a 'missing in action, assumed dead' notice."

SAS Rogue Heroes airs on BBC One on Sundays and the entire season is available on BBC iPlayer