WE JUST WANTED to have a party.

It was May 1993, and the Bosnian war was in full swing. I had been in the region for about five months working for a humanitarian-aid group called the Serious Road Trip. We transported food, medicine, and clothing from the Croatian port of Split to Sarajevo, which was under siege by nationalist Serbs and was probably the most dangerous city in the world. We dressed up as clowns and drove trucks painted with cartoon characters like Bart Simpson and Wile E. Coyote. The costumes made kids smile and helped us get through military checkpoints. At least, most of the time.

A Bosnian friend's band was going to play at an underground club, so my co-worker Graeme and I offered to buy vodka, which meant driving about 20 miles north of the city. Around noon, we rolled our old Land Rover—painted like a Rastafarian flag, with smiley faces on the hubcaps—up to the checkpoint on the only road out of the city. The haggard Serb soldiers waved us through.

When we returned, six hours later, they searched the Rastamobile and quickly found our 12 bottles of cheap Russian vodka under a pile of clothes in the back. They ushered us to a small concrete building and into a bare, rank room with a single window. Before shutting the steel door, an unkempt, bearded guard told us we would be sentenced in the morning for smuggling.

In Bosnia in the early nineties, every day felt like the day before you were going to get executed. But this time it was for real. A number of journalists and aid workers had been murdered in recent months, and now it was our turn. All for a booze run.

Within an hour, two guards barged into our room reeking of plum brandy. They pointed their Kalashnikovs in our faces, screaming, "You're going to die!" We cowered on our hands and knees, begging them not to shoot. They pulled the triggers. Click. No bullets. They laughed hysterically. Every hour or so they'd do it again.

Around midnight, mortar rounds shook the building. The Bosnian army in Sarajevo was fighting back. The guards were in our room when it started and loaded their guns. Now they were wide-eyed and sweating, just like us, and shouting with true anger: "Clinton is the devil!" "America is pigs!" Graeme and I tucked into a corner. The lightbulb went out and chunks of the ceiling rained down.

Finally, after a long period of silence, one of the guards exhaled loudly. Then, without really thinking, I did what may have saved our lives: I offered him a cigarette. I don't smoke, never have. I used cigarettes as a way to break the ice, though up until that moment only with "friendlies." The guard accepted, and as he smoked I brought up basketball, figuring he would like the L.A. Lakers, since their center, Vlade Divac, was a Serb. I said I was a Chicago Bulls fan, even though I wasn't. We all had a broken bilingual debate until dawn.

A few hours later, the guards released us. Machine guns crackled in the distance. One of the men gave us the keys to the Land Rover and, without saying a word, motioned for us to leave.

We drove back into the city, now being bombed by the people we'd just left. Graeme rifled behind the seats. "So much for the vodka!" he yelled.

Expert Analysis: While it's a good idea to clearly identify yourself as a noncombatant, the downside is that you are highly visible to anyone wishing to take a shot at you. And, in this case, not everyone will see the humor, especially if they're drunk. Cigarettes or other such commodities are as important as cash in these environments. And anything that isn't a delicate subject (like politics or religion) can be used to calm tense situations and open up conversations—it's always difficult to hurt or kill someone you know and have something in common with. —Tim Crockett, former Royal Marines commando and executive director of AKE Group, which trains civilians who work in hostile environments