When it comes to designing and building the new Williams and Mercedes Formula 1 cars for the looming 2024 season, there is precision and, most importantly, there is a plan. There has to be because all 10 teams are facing their first winter shutdown - a new ruling by the sport’s governing body, the FIA. But things don’t always go to plan - and the teams face a race against the clock to finish key bits of the car build before the Christmas holidays. Holly Samos and journalist Sarah Holt are going behind the scenes at two of the biggest names in F1, to the heart of their mammoth operations

One of the first hurdles for the teams to clear are the FIA crash tests. This series of tests is designed to ensure the safety of the sport, and crucially the drivers. However, for the teams they present one of their biggest challenges in the car build. At the Mercedes factory in Brackley they are waiting anxiously for news from the sport’s crash-testing facility at Cranfield University.

For the all-important drivers and team principals - the faces of Formula 1 - the winter is a chance to step back from the spotlight. For Williams star Alex Albon this is a time to reconnect with family while Lewis Hamilton has some thinking to do on his Christmas break in the U.S.

There are also holiday plans on the horizon for team principals Toto Wolff and James Vowles but the responsibility for the workforce back at base is never far from their minds. At Williams, Vowles knows his factory at Grove is preparing to dig deep - but what will he find when his workforce gets back to work in the new year?

F1: Back at Base is an IMG Production for the BBC Narrated by Joseph Fiennes Co-hosts & Executive Producers are Holly Samos and Sarah Holt The Producers are Alasdair Cresswell, Joe Aldridge and Jack Winstanley. The Senior Producer is Ollie Kneen The Executive Producer for IMG is Steve Tebb The Showrunner is Holly Samos The Story Editor and Scriptwriter is Sarah Holt The Commissioning Editor at the BBC is Stevie Middleton