Paul Biddiss, who trained Paul Mescal and Day of the Jackal star Eddie Redmayne, says streetwise women are more aware of surveillance and harder to follow

He has trained would-be assassins and marshalled invading hordes, Napoleonic forces and Roman regiments, but movie military adviser Paul Biddiss found himself in the midst of his biggest Hollywood skirmish last month when the actor Saoirse Ronan made a powerful intervention about women’s personal safety.

Ronan, a guest on Graham Norton’s BBC chatshow sofa, sparked a nationwide debate about women’s security fears when she interrupted fellow actors as they discussed techniques that Biddiss had taught the casts of both Gladiator II and the new drama series The Day of the Jackal.