Hey, hey, it's the monkeys

But these guys aren't fooling around. Nigel Benson previews Dark Days in Monkey City.

One of the most extraordinary wildlife documentary programmes to screen in New Zealand premieres tonight.

Dark Days in Monkey City visits a warring colony of toque macaques in the ancient Sri Lankan temple city of Polonnaruwa - known by locals as "Monkey City".

The decaying jungle city was once ruled by Buddhist and Hindu kings, but is now bossed by gangs of feisty monkeys.

The ruins of the crumbling temples are turned into a savage battlefield as the monkeys fight for supremacy and survival against predators like flesh-eating monitor lizards.

It is nature's own rumble in the jungle.

The 13-part series was created for Animal Planet by Dunedin's Natural History New Zealand film unit.

The toughest tribe in Monkey City is the Temple Troop, which staunchly defends the best real estate in the area at Fig Tree Vale.

Their main enemies are the neighbouring Black Claws, who will stop at nothing to conquer that territory so they no longer have to feed on a diet of human rubbish.

The monkeys grow to 35cm in length (excluding tail), weigh up to 8.4kg and operate in troops of up to 20 soldiers.

The tension between the groups grows as they head for all-out war.

Dark Days blends wildlife footage with special effects to show the animals' highly complex society, in which rank and hierarchy determine nearly every aspect of day-to-day life.

The NHNZ crew spent nearly a month at Polonnaruwa Nature Sanctuary and Archaeology Reserve in Sri Lanka filming the monkeys in front of big green screens.

It took a week to build a portable studio featuring backdrops and a small stage painted with a special shade of green especially imported from New Zealand.

Then the monkey business started, as the crew tried to entice the wild macaques on to the set for filming.

They shot sequences created through comic book-style story boards crafted months before the shoot.

"We knew exactly what we wanted when we went to Sri Lanka," series producer Ian McGee says.

"We had wonderful story boards and fantastic shooting scripts.

"The trouble is, the monkeys didn't read them.