A few years ago Les McKeown took me into a pub toilet. I was on the end of a phone line, interviewing him for an upcoming show in Nottingham, when he broke off to relieve himself in the gents.
I say "broke off"; he carried on talking. I only knew where he'd gone by the creak of the door and the echo of the bathroom and... well, I don't need to elaborate on the sound effects that followed.
He didn't apologise, didn't even mention it – but back then, the boozer was his office.
These days he keeps out of pubs, having quit the hard stuff 18 months ago.
"My mum and dad dying in 2002 was the catalyst for me entering self-destruct mode," says the 54-year-old Scot.
"I would drink a couple of bottles of 50% proof Wild Turkey a day.
"When I woke up the first thing I'd do was have a big glass of whisky and a fag. The only time I didn't drink was when I tried to stay a little bit sober when I was on stage."
His wake-up call came two years ago with a visit to the doctor.
"I had a liver function test and they said, 'you're going to die any day now – you've got to stop.'"
By coincidence, he was offered the chance to go on a TV show in the US called Celebrity Rehab, where stars were to fight their addictions on camera at Passages, a luxury clinic in Malibu, California.
Others included models Alicia Douvall and Cassie Sumner, Peter Sellers' daughter Victoria Sellers, Happy Mondays singer and X Factor finalist Rowetta Satchell and Robin Le Mesurier, son of Dad's Army star John.
"It was a reality TV show but the quality of care at this place was incredible," says McKeown. "I looked it up on the internet and people were paying a fortune to go into rehab there.
"I thought, well, I'm never going to be able to afford that; it felt like a last-chance-saloon type of thing."
It wasn't easy.
"Physically, I felt terrible. When you're drinking all the time, it's like an anaesthetic. You don't feel any of the damage you might have done to your hips or your joints. Once you stop you feel like you've aged five years.
"I've been exercising since then and I've just joined a gym where I have a personal trainer.
"I found it difficult sleeping. It took me six months to get back into any kind of a sleeping pattern.
"Before, I would get drunk in the morning, be asleep by 12 o'clock, get up for an afternoon session, be asleep again by five or six o'clock, then get up again for an evening session. I had that odd sleeping habit for years – well, it wasn't actually 'sleeping' so much as being unconscious because of the effects of alcohol.
"I still have some nights where I can't sleep but I get up and do some work, either answering e-mails or doing a song, and that seems to do the trick.
"Part of my new life was taking charge of my shows: the management, the agent side of it, tour-managing, booking hotels and dealing with PA companies... I've taken charge of all those elements because I wanted to fill up my days with positive things to do.
"It sounds quite mundane but it's quite complex and it keeps me busy 24/7."
He's writing a new album, his first featuring new material in 30 years.
"I would say it's like the Rollers but 30 years later."
In the 70s, the Bay City Rollers were Britain's biggest pop group, prompting an hysteria among fans, dubbed Rollermania, that hadn't been seen since The Beatles.
They notched up nine UK Top 10 hits including Remember (Sha-La-La) and Shang-A-Lang, All Of Me Loves All Of You, plus two number ones: Bye Bye Baby and Give A Little Love.
McKeown is the only original member of the group still touring and, as part of the Once In A Lifetime tour, he'll be reliving those days.
Expect him to be a better performer than previous shows
"I'm talking a lot more with the audience. I'm able to communicate with people on a level now, rather than being someone who is in their own little world, making jokes only he can laugh at."
Back in the day, the group weren't big drinkers.
"Apart from milk!" he laughs.
"I did binge drink post-Roller days, starting around 1978/79. But alcohol never played a big part in my life until 2002 triggered by my parents dying. I didn't realise that was what it was until I went in to rehab."
These days, there's no booze backstage. After a show the rest of his band go one way and McKeown heads to the hotel to watch the TV.
"I don't miss it," he insists.
"I don't think, Ah, they're all having fun, getting drunk. I'm quite happy. Psychologically I feel a lot sharper. I've a much more upbeat attitude."
Les McKeown's Legendary Bay City Rollers join The Osmonds, David Essex and Leo Sayer on the Once In A Lifetime Tour 2010 which comes to the Trent FM Arena, Nottingham on June 29. Tickets are £36.50, 08444 124624.