He'd decided to try his SUV in a little bit of cross-country travel, had great fun zooming over the badlands and through the sand, got lost, hit a big rock, and then he couldn't get it started again. There were no cell phone towers anywhere near, so his cell phone was useless. He had no family, his parents had died a few years before in an auto accident, and his few friends had no idea he was out here.
He stayed with the car for a day or so, but his one bottle of water ran out and he was getting thirsty. He thought maybe he knew the direction back, now that he'd paid attention to the sun and thought he'd figured out which way was north, so he decided to start walking. He figured he only had to go about 30 miles or so and he'd be back to the small town he'd gotten gas in last.
He thinks about walking at night to avoid the heat and sun, but based upon how dark it actually was the night before, and given that he has no flashlight, he's afraid that he'll break a leg or step on a rattlesnake. So, he puts on some sun block, puts the rest in his pocket for reapplication later, brings an umbrella he'd had in the back of the SUV with him to give him a little shade, pours the windshield wiper fluid into his water bottle in case he gets that desperate, brings his pocket knife in case he finds a cactus that looks like it might have water in it, and heads out in the direction he thinks is right.
He walks for the entire day. By the end of the day he's really thirsty. He's been sweating all day, and his lips are starting to crack. He's reapplied the sunblock twice, and tried to stay under the umbrella, but he still feels sunburned. The windshield wiper fluid sloshing in the bottle in his pocket is really getting tempting now. He knows that it's mainly water and some ethanol and coloring, but he also knows that they add some kind of poison to it to keep people from drinking it. He wonders what the poison is, and whether the poison would be worse than dying of thirst.
He pushes on, trying to get to that small town before dark.
By the end of the day he starts getting worried. He figures he's been walking at least 3 miles an hour, according to his watch for over 10 hours. That means that if his estimate was right that he should be close to the town. But he doesn't recognize any of this. He had to cross a dry creek bed a mile or two back, and he doesn't remember coming through it in the SUV. He figures that maybe he got his direction off just a little and that the dry creek bed was just off to one side of his path. He tells himself that he's close, and that after dark he'll start seeing the town lights over one of these hills, and that'll be all he needs.
As it gets dim enough that he starts stumbling over small rocks and things, he finds a spot and sits down to wait for full dark and the town lights.
Full dark comes before he knows it. He must have dozed off. He stands back up and turns all the way around. He sees nothing but stars.
He wakes up the next morning feeling absolutely lousy. His eyes are gummy and his mouth and nose feel like they're full of sand. He so thirsty that he can't even swallow. He barely got any sleep because it was so cold. He'd forgotten how cold it got at night in the desert and hadn't noticed it the night before because he'd been in his car.
He knows the Rule of Threes - three minutes without air, three days without water, three weeks without food - then you die. Some people can make it a little longer, in the best situations. But the desert heat and having to walk and sweat isn't the best situation to be without water. He figures, unless he finds water, this is his last day.
He rinses his mouth out with a little of the windshield wiper fluid. He waits a while after spitting that little bit out, to see if his mouth goes numb, or he feels dizzy or something. Has his mouth gone numb? Is it just in his mind? He's not sure. He'll go a little...