Celebrity Bear Hunt sees Grylls track the likes of Mel B and Boris Becker through the jungle to teach them about survival. Sam Wollaston travels to Costa Rica to see what it’s like – but things do not go to plan

I am slithering across the forest floor, stealthily, silently, like a pit viper perhaps? But that would make me the predator and I think I’m the prey here. Actually – to be honest – slithering and stealthily are wishful thinking; it’s more like trying to creep, a little stooped, in an attempt to be less visible to Bear Grylls, who is hunting me. Although – further honesty alert! – he’s not really hunting me. We’ll come to that.

I’m trying to remember what Grylls said in his brief about how to avoid detection. A lot of things beginning with S: sound obviously, though it’s hard to be quiet here because the forest floor is covered in dry leaves and twigs. Smell is another; wish I’d gone easier on the Lynx Jungle Fresh – hopefully Bear is upwind. Shadow, silhouette and shine are also no-nos, some of which Grylls himself helped with by rubbing dirt on my face.