Sarah Brett gets under the bonnet of F1's newest car with Lewis Hamilton and Valtteri Bottas at the Mercedes F1 factory. Nihal Arthanayake talks to ex-firearm officer Tony Long.

Sarah Brett is live from Mercedes F1 factory in Brackley as the team prepare their new 2017 car for its world debut. She speaks to designers, engineers and drivers Lewis Hamilton and Valtteri Bottas.

Meanwhile in the studio, former Met armed officer Tony Long discusses his new book Lethal Force with Nihal Arthanayake. Plus all the afternoon's breaking news, sport and conversation.