Hidden deep within an industrial estate in Paisley something is stirring. The acrid stench of burnt metal mixes with the sound of rending steel echoing through a cavernous warehouse. From the outside it looks so innocent but inside a dormant machine has awakened. Robot Wars is back. Bigger and badder than ever.

For anyone who doesn't remember the show that ran from 2001 to 2003 on BBC, before making a brief move to Channel 5 for a final season, it was the ultimate in geek gladiatorial combat as teams pitched their homemade robots against each other in a test of strength and power. A series of one-on-one matches as their mechanised warriors fought while trying to avoid deadly traps and the lethal 'house robots' (Sir Killalot, Matilda, Shunt and Dead Metal). Each match judged on damage inflicted, aggression and control of their robot if there was no clear winner.

You can hear the crunch of grinding metal before you even enter the arena. The 22 meter squared fighting pit is surrounded by 37 tonnes of polycarbonate bulletproof glass to protect the audience. Each death match a blizzard of circular saws, hammers, flippers and spinners. 'Now they have spinners, these arms that spin round at 3000 revs per minute, they do proper damage. They sheer off things. The number of times we've had things smash into the glass in front of us. Huge lumps of metal. You can see it just below you steaming, shrapnel basically,' explains new presenter Dara O'Briain obviously still hyped from the last battle.

'You are completely immersed in their world,' adds co-host Angela Scanlon. 'They've spent three years building a robot, painstakingly putting it together and it takes three seconds to demolish it in front of everybody. You can't help but be engrossed in that.'

When you enter the ginormous studio you are swallowed up by the revved up crowd, baying for mechanical carnage. Head house robot Sir Killalot is greeted like a rock star with a burst of Motörhead's 'Ace of Spades' over the PA. In person Sir Killalot is an intimidating beast. He's doubled in size since he was last on our screens 13 years ago. Now weighing in at a terrifying three quarters of a ton.

Behind the scenes the backstage pit buzzes with energy. This is a dream come true as the amateur roboteers tinker with their creations. Advances in technology have made their motorized marvels even more deadly, with custom 3D printed parts, lithium batteries and access to Hardox (ie hardened steel used in tanks), the house robots no longer rule the roost.

But once they leave the kill floor there's a real sense of camaraderie. 'In one fight one robot was taken apart, absolutely destroyed,' says O'Briain, 'and we came back later and there were four or five different teams gathered around one table welding pieces together to get that robot out again for the next fight.'

It's the contestant's passion and excitement that really makes Robot Wars so unique. 'We have a father and daughter team, and the girl was a Robot Wars baby. Her mum went into labour while watching her husband fight. She's back with her dad and his old team mate going through it all again,' says Scalon. 'It's kind of heart-warming and totally bonkers.'

Robot Wars returns to BBC Two, Sun 24 Jul, 8pm.