This series is about 24 hours in Helmand, Afghanistan's most violent province. I was with the Queen's Company, British soldiers who normally guard Buckingham Palace. Their job was to train the Afghan National Army while fighting the Taliban, an almost impossible combination. On the day this was shot, we were ambushed late in the morning, then surrounded in a small house belonging to a terrified Afghan family. The battle to get out of the house lasted eight hours. The two most senior soldiers there—both veterans of Iraq, Bosnia, Kosovo and Northern Ireland—agreed that it was the most intense day they had ever experienced. I spent two months in Afghanistan, and I'm sure that what I saw in Helmand is going on in many other parts of the country. We could be there for decades.