A total of thirteen episodes were broadcast over the course of two series, beginning with a feature-length pilot on 28 December 2001.

The series initially focused on lead character, Sergeant Jo McDonagh (Tamzin Outhwaite), who was nicknamed McDoughnut, but later series played out as more of an ensemble piece, with several notable characters coming to prominence.

[citation needed] A number of fictional regiments were featured in the series, including the Bedford Light Infantry, the Royal Cumbrian Fusiliers, the Wessex Regiment and the Derbyshire Light Infantry.

According to BBC sources, Outhwaite spent a week familiarising herself with Army life at the Reserve Training and Mobilisation Centre in Chilwell, Nottingham, prior to filming the series.

A BBC spokesman said; "With such experience, Patrick infuses Red Cap with a tangible sense of realism."