In July 2007, I visited a shaman by accident. My wife had an appointment with a therapist called Wendell and, unable to attend, she offered it to me. As I ascended the stairs in Notting Hill, I mused on the fact that I had once worked as a film editor at a company on Wendell Road in Shepherd’s Bush. I hadn’t thought about that job for years; it was before I became a father, a comedy writer, a musician and a voice artist – and developed the calm exterior that belied my turbulent, contradictory internal state. It had been 22 years but being cast back to that time made me shudder, as though a wave was passing through me.

As I stopped on the landing, the door opened. Wendell, an African-Caribbean man of about 40, stared at me in a way I didn’t expect from a welcoming therapist. He tilted his head to one side as if to say: “What’s the story?”

“Hello,” I ventured. “Sarah couldn’t come but thought it would be OK if I did …” Wendell kept staring. He seemed wary and on edge. “Why?”

It was a good question. Before I had a chance to answer, or even think of one, Wendell said: “There are two of you. There are two of you here.” My instinctive reaction was to do a comedy double-take over my shoulder, but I didn’t. Something in Wendell’s demeanour was marrying with my odd thoughts and memories on the way up the stairs. And what he was saying made sense.

In retrospect, what I think was happening as I climbed the stairs was that the homunculus inside me, realising it was close to a presence that threatened its existence – Wendell – was awakening. I realise that makes me sound, well … unsound – but I have had a long time to think about this.

Anyway, Wendell beckoned me into his room and asked me to tell him what was on my mind. So I told him everything about being abused when I was a child – or rather, gave him a 20-minute precis.

“He’s here, he’s here with you,” said Wendell, with absolute certitude. I experienced an intense sensation of anxiety, as if someone had released a bag of chaffinches into a hitherto unknown cavity inside my chest. Wendell calmly explained that as well as being a therapist, he was also a shaman. Did I know what a shaman was? I said I thought so. Wendell explained further that he could perform an exorcism and rid me of the presence he had detected inside me.

There was a flat, padded platform in the centre of the room, a bit like a massage table, and Wendell suggested I lie on it. He asked me to trust him and said not to be scared by anything I might see or hear. I had seen a couple of therapists and the odd counsellor in the past for a session or two, long enough to con them (or at least con-vince them) that I was fine. This felt nothing like that. There was no tinkling water feature, meditative music or whale-song. This was just a very simple, third-floor room in west London, through the windows of which I could see the branches of leafy plane trees and hear the sound of passing buses.

Wendell asked me to tell him more about my abuser. None of it came out in order. Rather, there was a series of unconnected sentences. It felt as if the information was being proffered by a presence inside me, hoping each nugget would satisfy Wendell’s curiosity. I felt powerless over what was being said, but the longer the litany went on, the more I felt a swelling in my chest.

And then I began to cry. And cry. And cry. Hot streams of tears flooded over my cheeks and round my neck. I was silent but shaking, as the massive swelling in my torso seemed to pump tears endlessly.

“Pffffffftttttt.” Wendell spat a dry, sharp noise from pursed lips, like the sound of an arrow flying then hitting a target. There was a rattle from a gourd filled with seeds. Wendell moved around the table and my sobbing form, his legs bent at the knee, almost prancing.

He shook around me like the wind, like a kite on the wind, like a shutter clattering – all the time flitting around me, the bed, the room. I cried harder and harder, the swelling now felt as if it wanted me to eject it and all the time the “Pffffffftttttt”, the shaking of the seeds, the concentrated, forensic attention as Wendell did battle.

Suddenly, my chest seemed to be opening, accompanied by a roaring sound like a plane taking off. I felt an endless column of light rushing and roaring upwards from me – upwards, upwards, pulling me, yet all the time I felt Wendell ensuring I stayed. He was flying about me, his actions, sounds and will all furiously co-ordinated as the column of light gained infinite height. The roaring intensified, the light poured out of me, burning everything to white.

Silence.

“He’s gone now.”

Wendell was sitting on a chair close by. I was shaking with the aftershocks of so much crying, shuddering like a toddler. Something fundamental had shifted within me. Although it would be years before I was able to understand the occurrences and consequences of my abuse, this was the beginning of the process. I can’t be sure of what actually took place in that room. I can only say how it felt. It was painful and raw, like a clumsy initial rooting around to extract shrapnel, but it was a necessary start. Even if it had happened by accident.

• Shadowman: Records of a Life Corrupted by Johnny Daukes is out now (Red Door Books, £12.99), as is an accompanying album of 11 songs, Shadowman: Records Remade

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