Heston's Mission Impossible

Heston boards the nuclear-powered Royal Navy sub, HMS Turbulent, to shake up the sailors' food.

It's not long before Heston realises he's got a big job on his hands: the men are out on patrol for 90 days at a time, and they're eating three stodgy meals a day. And with so little opportunity for exercise on board, it' not a healthy diet - especially when the submariners' jobs require very high levels of concentration.

But how is Heston going to change it? Heston researches the effects of food on the brain. He develops recipes with brain enhancing ingredients - blueberries, mackerel and dark chocolate - but his first food roll-out goes down like a heavy submarine.

For his second attempt Heston replaces the traditional Friday fish and chips, using the cod tongues and cheeks to create 'tongue and cheek' scampi. But the Captain's not impressed.

Heston and his team have a big rethink and come up with a radical new idea - a cooking and storage technique, sous vide, that they use in Heston's restaurants to create the finest meals.

But it would mean a total revolution in the way the navy prepares its food. Will Heston be able to persuade the Captain of HMS Turbulent that this is the way forward?

Clips from Episode 4

• S1-Ep4: Brain Food

• All Clips (1)