Although I wanted to reach Samantha in the shortest time possible, after walking on for another two and a half dry, dull and dragging hours I knew that I would have to stop and rest. As I had already admitted to myself on a number of occasions since starting the mammoth walk, spending a little time with Sam was infinitely preferable to spending no time with her at all and I knew that if I didn't stop for a while then I would be burnt out before the morning sun appeared.

The boredom of my march combined with the overpowering heat and a lack of distraction to devastating effect to leave me feeling numb and exhausted. In all the time that I had been out on the roads, I could only have seen four or five people in the darkness and they had been little more than shadowy figures in the distance, not one of them had been close enough to speak to. The countryside through which I walked was quiet at the best of times and I could not recall having passed even a single building in the last hour.

Although I had not deviated from the route which I had planned to follow, as I stumbled along my mind began to play dangerous tricks on me. I had concentrated such effort on getting to Samantha and keeping the prescribed path that I suddenly began, quite irrationally, to convince myself that I was on the wrong road. The fear inside - which grew steadily with each passing mile - was not so much that I might be following the wrong road, it was more that the monotonous, gloomy and repetitive landscape offered nothing in the way of confirmation that I was on course. I began to think that if I had made a mistake with my clumsy map reading, then the chances were that it would be far too late to be able to do anything about it now. I knew that I was working against a clock that was quickly counting down time against me and I also realised that an error now might mean that I would never reach Samantha before the end. Eventually, in a desperate attempt to rest my body, clear my mind and satisfy myself that I was heading in the right direction, I stopped for a while.

I stood at the roadside and looked around for somewhere to rest. I soon realised that, as there were no cars to worry about anymore, it didn't matter where I stopped, and so I dumped myself in an unceremonious heap on the hard kerb stones which lined the sides of the sticky tarmac road. Feeling the tiredness flowing out of my weary body, I let myself fall back onto the dry grass verge and I lay there in an exhausted silence, staring up into the dark sky above me. I heard the sudden, crunching sound of footsteps on brittle grass in a nearby field and, rather than get up and investigate, I simply chose to lie still and wait until the noise had passed me by. I screwed my eyes tightly closed, hoping that I would be left alone to relax in peace.

'Evening, mate,' a gruff voice said, startling me and shattering the silence. I cautiously opened one eye and saw that a face peered down at me from over the top of a hedge which separated the road from the fields beyond. The face belonged to a man who appeared to be around the same age as my father. A bushy, white beard gave him the appearance of a harmless and unseasonal Santa Claus and I sat up, suddenly glad of a little company. I collected my belongings together and acknowledged the amiable man.

'All right?' I asked. 'How are you doing?'

'Oh, I'm not too bad,' he said in a deep, dry and throaty voice. He seemed unable to control the volume of his voice and, although I was only a couple of feet away from him, I felt sure that I would have been able to hear his every word if I had been a mile further up the road.

'I don't want to seem like I'm beggin' or nothin',' the man continued, 'but you wouldn't 'appen to have something to drink in your bag would you?'

The man's lack of diction and his rustic accent were strangely endearing and I agreed to share a little of the bottled water which remained in my rucksack with him. I hoped that I would be with Samantha soon after daybreak and I felt sure that I wouldn't need all that I carried in the bag. My new companion walked away from the roadside and back into the field and I followed him.

The man dropped to the ground, sat on the grass for a moment and then lay back and looked into the star-filled sky above us. I stepped over the tow hedgerow and walked towards him across the brittle grass. The feeling of the dry, hard ground under my aching feet reminded me of the time I had spent with Samantha in the field and it was hard to believe that it had only been two nights ago. So much had happened in the meantime that it felt as if we had been apart for months. As I walked towards the man I made a silent vow to myself that in a further two days' time I would be holding Sam close to me once more.

I sat down on the rough ground and pulled the rucksack from my aching shoulders. I undid the straps and fastenings, took out what little food remained and drank from one of the last remaining bottles of water. I passed the half-drained vessel over to the man who raised himself up onto his elbows and emptied the plastic bottle in two gulps.

'That's better,' he said as he wiped his mouth dry with a dirty hand. 'I appreciate that, mate.'

'It's all right,' I said quietly.

After a couple of silent minutes had passed, the man spoke again.

'Where you headed?' he asked.

'To the coast,' I replied. 'I'm trying to reach my girlfriend.'

'Better hurry then,' he said and he started to laugh. 'I don't think you got that long left!'

'I know.'

I looked over at the man who lay on his back with a wide, lazy smile plastered across his face. Even if his conversation was less than stimulating, the company was a welcome interruption to the dark monotony of the stifling night.

'What about you?' I asked. 'Where are you going?'

The man shrugged his shoulders and, for no immediately apparent reason, began to laugh again.

'Dunno,' he said. 'I'm just walking around.'

'Isn't there anyone that you want to be with?' I asked, cautiously.

'Nah' he grunted. 'I've just walked out on her.'

The man turned his tired head and, seeing the puzzled look on my face, began to explain.

'I've been married to a real cow for nigh on thirty years. I never had the bottle to get up and get out until tonight when I just decided to go. I figured that the end of the world was as good a reason as any to leave and that was it - I just got up and went.'

He lay back down on the grass, chuckled and then began to laugh uncontrollably once more.

'You should'a seen it!' he roared. 'Right in the middle of dinner it was. I just got up and pissed off!'

I smiled and then began to laugh. Soon, and for no real reason that I could think of, I was laughing as loudly as the man at my side.

'Should've seen 'er face!' he screamed, the tears rolling down his dirty cheeks.

'The world might not end,' I said, trying to be more serious. 'Things might get back to normal. What are you going to do then?'

He wiped his eyes and, for a fraction of a second, a look of intense and obviously false concern spread across his face.

'It bloody better end,' he said, trying not to laugh again, 'If it don't then I'm really in the shit!'

I took off my T-shirt and wiped my sweat-covered face on it before throwing it over my shoulder and into the hedge. I lay back down on the hard, moistureless ground and stared up into the stars. It was a beautiful, clear night (now that I thought about it, I realised that I had not seen a cloud for days) and I could not help but notice how normal everything looked. The man at my side was quiet for a moment.

'It's definitely going to end,' he said, suddenly.

I turned my head to the side to look at him. He remained flat on his back with his eyes closed and his hands behind his head.

'There ain't no question about it,' he continued. 'Things don't get this bad and then get better again. This really is it.'

I knew that he was right and returned my attention to the skies above us. I thought back to the energy pulse earlier in the day and it was only then that I realised the extreme danger that we were both exposed to. Should another one of the deadly waves strike now, there would be no escape from the heat, light and wind. Should the wave be as strong or, as seemed to be more likely, stronger than the last, then neither of us could expect to escape with anything less than extensive and dangerous burns. I still carried my wide umbrella but the protection that would afford me was negligible. If the next pulse was stronger, I thought, then perhaps even shelter and shade would not be enough to prevent severe injury and damage. Walking along open roads to reach Samantha was a calculated risk that I had to take but lying here, exposed and vulnerable in the empty field, was little short of foolish and stupid.

As I lay still, I thought more about the pulses and their timing. The first and second waves had been separated by a week, there had been three or four days between the second and third, and under two days between the third pulse and the one which had struck yesterday. If the gaps between the pulses continued to reduce (and I had no reason to think that they would not) then there was a real chance of at least one more wave striking later today. As the realisation began to dawn on me, it gave me a new impetus to reach Sam quickly.

I got to my feet and shook the dust from my damp, ragged clothes. The man at my side began to snore and I wondered if I should wake him rather than leave him exposed and at the mercy of the heat and light. Although I tried to think about other things, as I readied myself to leave I could not help but wonder when the pulse would strike the planet that would have the power to burn and kill. I knew that I could waste no more time.

I gently kicked the man's side and he fidgeted on the ground at my feet. Mumbling and groaning at having been disturbed, he looked up at me through tired eyes.

'I think you'd better get yourself under some cover,' I said, genuinely concerned for my companion. 'There might be another one of those energy waves before long.'

He stared at me for a moment before closing his eyes again and smiling to himself.

'That's all right, pal,' he said as he stifled a yawn. 'If we've got to go, we've got to go.'

Although I could not help but admire the man's attitude, I almost wanted to grab his arm and pull him under cover. I had to accept, however, that staying there was his choice and his choice alone to make. Looking back, I was perhaps a little jealous of how the man was able to relax and to almost enjoy the end of the world while I seemed destined to spend the rest of my time dragging myself along endless roads.

'Well I'm going,' I said, annoyed with the man and with myself. 'If you want to stay here then you can. Hope you enjoy it.'

The man began to snore again and I left the field. I clambered over the low, prickly hedgerow and back onto the quiet road. Before hauling it onto my aching shoulders, I checked the contents of the little bag that I carried and I found that only a few scraps of food and one more bottle of water remained. There was one clean T-shirt in a side pocket and a pair of running shorts. I changed into them and dumped my soiled clothes carefully at the side of the road before moving off.

I had made reasonable progress throughout the day and I looked at the map as I walked along the road. The light from the moon was just bright enough to enable me to make out the majority of the details on the map and I saw that I had covered roughly half of the distance between where I had left the car and Samantha's grandmother's house. I tore the map in half, keeping only the relevant part, and screwed the rest up, throwing it down to the ground. I folded up what remained of the map and shoved it down the back of my shorts.

Once I was sure that I was heading in the right direction (leaving the field had proved strangely disorientating) I walked on through the night. The only sounds came from my tired feet dragging on the ground and from the metallic tip of my umbrella-walking stick hitting the dry road.