Mel C says she was sexually assaulted the night before the first Spice Girls concert

One of the Spice Girls is reckoning with a painful memory. Melanie Chisholm, a.k.a as Mel C and Sporty Spice, has a new memoir out soon. Ahead of that book's release, Chisholm appeared on Elizabeth Day's podcast How To Fail, and recounted a traumatic experience from the beginning of her career with the iconic girl group.

When the Spice Girls were first coming together in 1997, their first-ever live performances took place in Istanbul. While staying at a local hotel, Chisholm experienced something that she didn't make sense of for years.

"We'd never done a full-length concert before, so obviously we'd rehearsed for weeks ahead, costume fittings, makeup, hair, everything was leading towards the pinnacle of everything I ever wanted to do, and ever wanted to be," Chisholm told Day on the podcast. "What drives me is being on stage, being a performer, so here we were, the eve of the first-ever Spice Girls show, so I treat myself to a massage in the hotel."

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Chisholm continued, "And what happened to me — I kind of buried, immediately, because there were other things to focus on. I didn't want to make a fuss but also I didn't have time to deal with it. Because I didn't deal with it at the time, I realized I allowed that to be buried for years and years."

But then, when she was writing her memoir, Chisholm said that the experience came back to her "in a dream, or I kind of woke up and it was in my mind. And I was like, 'Oh, my gosh, I haven't even thought about having that in the book.' Then, of course, I had to think, 'Well, do I want to reveal this?' And I just thought, actually, I think it's really important for me to say it, and to finally deal with it and process it. Terrible things happen all the time and this situation wasn't as bad as it could've been...I suppose it's a 'mild' version of sexual assault. But I felt violated. I felt very vulnerable. I felt embarrassed."

Day thanked Chisholm for sharing her story, both on the podcast and in the book, and said that it was a good example of how "if something feels wrong, then it is wrong."

Chisholm's memoir, titled Who I Am in the United Kingdom and The Sporty One: My Life as a Spice Girl in the United States, will be published later this month in both countries.

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