This summer, Kiss fans will see the band take to the stage for the final time, introduced – as always – as “the hottest band in the world”. Despite remaining the undisputed kings of rock and roll theatre, with their elaborate costumes, demonic face paint and propensity to breathe fire over the audience, the group are stopping touring.

“I’m sure it’s going to be a multitude of feelings,” says Gene Simmons, singer and bassist. The flamboyant musician, now 73, is characteristically upbeat about bookmarking their touring career. “It will be thrilling,” he says.  “A sense of accomplishment – 50 years, half a century of doing this, defying the critics, many of whom have become mulch!”

The story of the New York band, co-founded by Simmons and guitarist Paul Stanley in 1973, is one of the underdog winning out.  What many initially dismissed as “shock rock” has become one of the biggest musical franchises of all time, with more than 100 million records sold worldwide and a dedicated museum in Las Vegas.  “For me it’s going to be that sense of pride of having gone up to Mount Olympus and scaled the heights and defied all the odds,” says Simmons.

The band’s final UK dates, part of their End Of The Road World Tour, were originally planned for 2021 but postponed due to Covid-19. But on July 8 this year, they play the Ovo Hydro in Glasgow.  When their final live dates are over, Kiss’s legacy will live on – even through the band’s vast range of often bizarre branded products. “The sense of pride is probably going to prevail above at all because of having 5,000 licensed products – everything from Kiss condoms to Kiss caskets,” says Simmons.

“We’ll get you coming and we’ll get you going,” he adds with a booming laugh.

“Literally no other band has ever done what we’ve done. But that was not the intent. The intent was just to look inward and put together the band we never saw on stage.”

Simmons is famously one of the few teetotal rock stars of his generation. His laser focus on the music and spectacle of the Kiss live shows has been a driving force for the group. “Our whole thing was always a self-mandated idea of putting together the band we never saw on stage,” he says, reflecting on their years together.

“It’s partly music and partly making a spectacle out of yourself. That’s what it’s about. This stage is for the few. Most people are afraid to get up on stage because they will be judged – and they don’t want to do that. You’ve got to have a loose screw to be up on that stage.”

Kiss have achieved many milestones over the years, from being inducted into the Rock and Roll Hall of Fame to their collection of awards. What is left?  “The real award is when a fan stands in an endless line and puts down their hard-earned money to buy a ticket,” he offers.  “That’s the most valued award because somebody had to work for that. There’s a responsibility. We have to give them bang for the buck and a kick in the n**s.

“You have to remember for half a century we have been introducing ourselves with:‘You wanted the best, you got the best – the hottest band in the world’. It’s a lot.  “It was b****y for a new band that had no resume, achieved nothing, never been anywhere, never been anywhere outside of New York as a matter of fact, to think globally like that. I don’t know where it came from. It just happened.”

With the band retiring from the stage, there is the question of what will happen to their elaborate costumes, so beloved by fans.  Most will go on display, most likely at the museum, but there are copies in case a biopic ever reaches the screen.

“You have to understand that I’ve been wearing more make-up and higher heels than you ever wore in your life,” he jokes.  “Literally, my platform heels are seven inches tall and the dragon boots, each of them weigh as much as a bowling ball.  “And by the time you finish adding up the bass guitar around my neck and the armour and all that, it’s about 40 pounds. I’ve spit more fire on stage than any human being.”

Simmons is looking forward to the UK leg of Kiss’s tour, which begins in Plymouth in June.  “Were it not for The Beatles, England would have been about Knights of the Round Table and Guy Fawkes and all this other stuff – just another country with a history, and lots of countries have colourful histories,” he offers.  “The Beatles made it, and created a culture, almost a religion, and Liverpool became a holy ground ... so when The Beatles hit, it was like an H-bomb.

“I just couldn’t believe what I was seeing and hearing, it was unbelievable, and all of us kept pointing back to England and it affected me so much that I actually started to speak in a fake English accent.”

He does, however, marvel at people’s attitude to the weather in the UK. “In California when it starts raining they think it’s the end of the world ... But over there in Blighty it’s raining and nobody’s got an umbrella – they are soaked.

“Their sneakers and whatever else are filled with mud and they’re happy ... Unbelievable.”

And what about Simmons’s plans? Will he continue to make music, or even make a foray into public life? “Politics can’t afford me,” he says with a chuckle.  “They would hate me because I would tell the truth and I wouldn’t care who I p***ed off. No, we have the Gene Simmons Band and I enjoy playing live so I fully intend to go to the shows, not because I have to, just for fun.”

Simmons is also quite the prolific businessman with a restaurant chain called Rock & Brews, casinos, a film company, a real estate entity and much more. He is not likely to be lacking work in retirement.

“But I will never get the thrill that I have had, the privilege of being in my favourite band for the last half a century,” he begins.

“There is nothing like it. We literally have more fun than the Pope.”

Kiss’s End Of The Road Tour plays at the Ovo Hydro, Glasgow on July 8 robomagiclive.com/kiss