Features

Andy McNab on the South Pole trek that inspired Cold Blood

'This vast area of nothing, as big as Europe, with the constant drift of ice creating shapes before your eyes'

Andy McNab on his South Pole trek

We were in three tents of five, crammed in to help generate body heat. The first three or so hours of each day were spent melting ice on the pressure cookers and trying to fill water bottles and eat and drink as much as we could. Trekking in Antarctica, at temperatures averaging -35C, you need about 8,000 calories a day.

On days that the temperature went down to -50C, it was really hard to breathe and to generate body heat. You try to keep everything covered up but if there's even the smallest chink in your clothing, you get windburn. We had a doctor with us who would treat these burns using something which generated new skin underneath, our version of an Antarctic facelift.

Even though we tended to walk in silence, preserving our energy during the day, once we were tucked up in our tents at night, the banter got going. In some respects it wasn't that different from my days in the army. You had to pee into a bottle rather than leave the tent, you had to take everything with you, leaving nothing there, just as we had to during hard routine as a special forces soldier. I probably found bagging up all my bodily deposits and happily letting them freeze in my pack rather easier to deal with than others!

For the final couple of days we started making out a shape on the horizon. It never seemed to get nearer, but eventually we got there, the Amundsen-Scott base that's at the South Pole. To stand on that spot, and to think of who - and how few - had been there before you, was an incredible feeling.

We were then stranded at the base due to bad weather for several days before we were able to begin the journey back to Chile. This gave me the perfect opportunity to start thinking about how I could use this extraordinary experience in the next book. I knew that the ice and the expanse of emptiness was more than it seemed, and that is always a good starting point for a thriller. I had just one problem though. The South Pole is a bit bleak and barren, no polar bears there, and I thought we could have some fun getting Nick Stone in front of a new kind of predator. So I switched the backdrop from the South Pole up to the North, just as much ice and cold, just a few more furry friends!

So I got that squared away, leaving me with just one other issue to sort out whilst waiting for the plane. What was I going to buy my wife in duty free that was going to make up for missing Christmas after all...

Sign up to the Penguin Newsletter

For the latest books, recommendations, author interviews and more