A handful of them gathered in the hot, early-evening sunshine to grab the best spots. Rods were assembled and laid on rests, gas stoves came out, chairs unfolded, and bivvies (a kind of 'Arabesque' green umbrella contraption with sides) erected, ready for the night ahead and in many cases, the days to come. Some planned to stay until Sunday evening.

The best spot (as it turned out) on the smaller of the two ponds, just 30 yards by 40 yards, happened to be in the corner under a set of traffic signals and a yellow sodium street light, no more than 10ft from the A24's four lanes.

In the gathering darkness, even towards H-Hour at midnight, there was no let up in the thundering traffic. The traffic of couples pausing for a snog in the semi-darkness and wobbling drunks from the Windmill pub along the road, grew steadily after chucking-out time. None of this troubled the fishermen whose anticipation reached fever-pitch. Most were overcome. Many lines were in the water by 10.30pm.

'I wanted to wait 'til midnight, but couldn't,' said Lee Noble, 16 (who had spent four quid on a mini-cab from Vauxhall). 'I was nearly wetting myself with excitement. I'd a GSCE this morning, then it was big rush to get everything together. If you're a fisherman the start of the season's a great moment. It's the prospect of the thrill of watching your float dip, catching a fish and playing it in.'

As to the best bait and what fish would take it, opinions inevitably differed - fruit-flavoured chunks of luncheon meat, liberally supplemented by handfuls of honey-coated sweet corn tossed on to the water, had a strong following.

Concensus said there were bream, roach, tench and carp. But, when it came to the real quarry, the perhaps-mythical big fish of Clapham (the one that got away), there was any number of stories. 'It's a 16lb 8oz carp and it's got one eye where it was foul-hooked,' said Lee.

'Yes, it was a 17lb carp, said Tim Collins, 37, a window cleaner from Stockwell. 'But it had two eyes and went by the name of Old Blackie. I had him on for 45 minutes last year,' said Tim, moments before he brought in a 9lb 8oz mirror carp. 'He towed me all round the lake, but got off. He's a little shit. I think if anybody got him in they'd die.'

Les Paine, 59, ready for all eventualities with mobile phone, is convinced it is a 20lb catfish, not a native of the lake at all. 'Someone probably had it in their aquarium and dumped it in there,' he said, adding, without a trace of irony, that 'lots of people have hooked it, but it always gets away.'

That wily, monster fish, whatever its species, is not the only monster of the deep ready to claim tackle. Les, from Clapham, and his son Gary, last year waded in and pulled out deck-chairs, shopping trolleys, dustbins. You name it.

But for the fishermen, who religiously and seemingly incongruously treat the fish with care and return them after weighing, there had been a more insidious evil stalking the urban jungle: the Vietnamese and Burmese living at the nearby bed-and-breakfast hotel for the homeless.

'They'd been stealing the carp to eat them,' said Les, an ex-Para. 'They were dragging it with traps made out of serrated baked-bean tins on the end of a rope. We caught four chaps who'd already got the car boot full and took them to the police. But the police let them go.'

Carp apart, another reason that some choose to sit on the grassless banks of this pond, in preference to the more secluded ones in mid-common, is safety. 'It's dangerous on the common, said Chris Brown, 40, an undertaker in Brixton. 'People get mugged and stabbed all the time. That's why we sit under the light.'

To emphasise the point, Colin Pettit, 31, from Brixton, reached inside his jacket and pulled out a meat cleaver. 'It's for chopping bait and hammering in tent pegs,' the demolition man said, a glint in his eye. 'But I'm a bit paranoid. That's why we come in a group so when you're tired the others can watch the gear. Otherwise you're liable to fall asleep and wake up with it all gone.'

As Colin and his brother Tony joked and chatted (a practice that would be frowned on elsewhere by serious anglers), slurred shouts 'Col, Col . . . Col' came from the darkness - the sound of a would-be angler, sprawled on the bank, line in the water, completely pissed.

'He's been out on the drink all day, got home and realised it was the start of the fishing season,' said Tony, 36, who purveys ornamental koi carp at his Brockley pet shop.

'It's like he's on automatic pilot. He got here with no bait, no nothing, and he's been bumming off us. He's got a couple of bottles of vodka in him. He'll wake tomorrow and wonder what's happened.' But at least he made it.

(Photographs omitted)