The actor clears up her character's controversial decision to remove her helmet.
The upcoming series will star Vicky McClure, Sheridan Smith, Martin Compston and Joe Cole.
The BBC's Line of Duty has found an unlikely fan in the shape of best-selling author Stephen King.
The series focuses on counter terrorism policing and the work of the Metropolitan Police Bomb Disposal Squad.
The Cheshire parish council clerk whose Zoom antics went viral earlier this year was drafted in to help host Jack Whitehall introduce opening act Coldplay.
Strictly Come Dancing judge Shirley Ballas has shut down rumours that Carrie Symonds will appear on this year's series.
The stars of the BBC crime drama promised to all get AC12 tattoos if the show got 12 million viewers.
Martin Compston is from Greenock in Scotland, which came as a surprise to 'Line of Duty' fans.