"The police and the army were all carrying guns. There was a real edginess to it all." How a "feral" Ozzy Osbourne crowd, an onstage meltdown, and some ill-advised nudity on live TV sparked a police manhunt for a British rock star in South America

In September 1995, the Monsters Of Rock visited South America for the second time. Once simply the title of a one day, one stage hard rock and metal festival held at Donington Park in England, from the mid '80s the franchise started to expand into new territories - mainland Europe, the US, the Soviet Union, and from 1994, Argentina, Brazil and Chile.

Kiss, Slayer and Tony Martin-era Black Sabbath were the marquee names atop the bill the first time the Monsters Of Rock stomped into South America, but the 1995 line-up was considerably heftier, with Ozzy Osbourne, Alice Cooper, Faith No More, Megadeth, Paradise Lost and Therapy? among the international stars on the campaign. For Therapy?, who would play 101 shows in 1995, their first ever visits to São Paulo, Rio de Janeiro, Santigao and Buenos Aires represented golden opportunities to showcase their recently-released third full-length album Infernal Love to their expanding international fan-base. But they had no idea what truly lay ahead.

To an outsider looking in, Therapy? were on the cusp of promotion into rock's premier league in 1995. The Northern Irish trio's second album, Troublegum, a top five hit in the UK, had sold 650,000 copies worldwide in 1994, and been acclaimed as the Album of the Year by Kerrang! magazine. In August 1995, in recognition of their burgeoning profile, the band - vocalist/guitarist Andy Cairns, bassist Michael McKeegan and drummer Fyfe Ewing - played as hand-picked special guests to Metallica at their Escape From The Studio headline show at Donington, above the likes of Skid Row, Slayer, White Zombie, Slash's Snakepit and Machine Head. Their record label, A&M, was confident that, at minimum, Infernal Love would be the band's first million-selling album, and their passport to a worldwide breakthrough.

Behind the scenes, however, Therapy? - and frontman Cairns in particular - were struggling with their new-found status and the accompanying pressure. Sections of the UK music press had turned on the band - "Almost every week there was a dig at Therapy?," Cairns recalled. "Initially it was funny, then it was despairing... cruel" - and cracks were starting to show.

"I was simply lost," Cairns admitted in a 2016 interview with The Quietus, recalling that he was self-medicating heavily at the time with alcohol and drugs. "I’d gone from being someone from County Antrim who played in a band, to travelling the world and being under lots of stress.

"At that point we had a massive operation on the go with management, the label, the crew. People had bought houses on the back of working for us. All of a sudden I’ve got technicians sitting at the back of the bus saying, 'I hope you’re writing more hits, mate, as I’ve got a mortgage to pay.'

"There was also this sense of not knowing who to trust. And moreover the band, who’d basically been a support group for each other since 1990, weren’t talking… not at all. I was a single man. There was no-one I could phone and say, I think I’m in trouble here, and I really need to talk."

In retrospect, a first visit to South America supporting a rock legend with one of the most rabid fan-bases in the world was always going to be an intense experience. And in Santigao, Chile, things boiled over alarmingly.

"The police and the army were there, and they were all carrying guns," recalled Michael McKeegan in Louder writer Simon Young's excellent authorised Therapy? biography So Much For The 30 Year Plan. "There was a real edginess to it all."

Whereas the opening date of the Monsters of Rock trek was staged in a São Paulo stadium, the sole Chilean date was booked into the 7,000-capacity Teatro Monumental. Inside the theatre, from the moment the doors opened, the atmosphere was charged, with Michael McKeegan remembering it as "the most feral crowd I've ever seen."

"The gig was like playing in Mad Max Beyond The Thunderdome," he told Simon Young.

"People were leaping from the third balcony into the moshpit," Andy Cairns recalled. "It looked like a Hieronymus Bosch painting... a seething pit of denim and skulls."

"Michael and myself were watching at one-point and saw this guy go ‘Smack!’ onto the concrete," touring cellist Martin McCarrick, later a full member of the band, told Hot Press magazine in 2003. "I’d be amazed if he didn’t break his back."

"All the bands were continually getting spat on," Cairns told me. "I'd had a few drinks before we went onstage and half-way through the set, when the spit get coming, I just stopped a song, dropped my trousers and started waving my cock about. That really annoyed the crowd for some reason, so obviously I kept doing it."

If the crowd inside the theatre were offended, so too were thousands of Chilean citizens watching the gig live on television. And at some point, an order was given to the local police to apprehend the exhibitionist rocker.

"The next day we were playing in Buenos Aires and so we decided to change our flights to get there earlier," Cairns recalled. "When we bumped into [Faith No More vocalist] Mike Patton there he said, 'You guys were really lucky', because apparently about two hours later the cops had turned up at the hotel to arrest me for indecent exposure.

'I don't think I'd have enjoyed a stay in a South American prison."

"We're banned from playing Chile again, apparently," Michael McKeegan told Young. "The crowd was great, but the spitting was too much."

“It was like playing in the ninth circle of hell," Cairns concluded.