It’s everybody’s dream to make money in their sleep, and a Welshman known as the ‘sleepwalking artist’ has done just that, the Independent reports.

Forty-year-old Lee Hadwin has astonished doctors and scientists by producing stunningly detailed artworks in his sleep, which he cannot reproduce when awake. “The thing that’s baffling the sleep clinics is that I cannot produce the same things when I’m awake,” Hadwin admits.

The artist told the Independent that he started drawing in his sleep when he was a child. As he reached his teens, his drawings became more and more detailed. “I drew the Marilyn Monroe pictures and in the morning I just looked at them and thought ‘Oh wow!,’” he said.

The former care worker’s artworks have become so popular that he has given up his day job to focus on his nocturnal art practice. The American entrepreneur Donald Trump owns one if his works, and the Marilyn Monroe Museum in Los Angeles recently bought three drawings for over £4,000 ($6,000).

However Hadwin has struggled to gain critical acceptance by the arts establishment due to his unconventional creative process. “I have never looked at myself as an artist,” he said. “But in the last few years I have decided to stop feeling guilty about it.”