The Northern Irish writer made sporadic appearances in a number of TV shows, including as a wildling in the hit series Game of Thrones back in 2016.
However, it was writing where the University of Cambridge alum was perhaps best known, as he put together the mini drama series My Left Nut.
The Belfast-born man was diagnosed with Motor Neurone Disease in 2023, with the neurological condition also claiming the lives of both Professor Stephen Hawking and rugby league star Rob Burrow in recent years.
After a short spell in the hospice, his wife Naomi confirmed that he had passed away on 7 April 2026.
She wrote: "Last night, Mick sadly passed away in the Northern Ireland Hospice.
"He was admitted 10 days ago and was cared for by the incredible team there. He passed peacefully surrounded by family and friends.
"Words can’t describe how broken-hearted we are.
"It’s been said more than once that Mick was an inspiration to everyone who was privileged enough to come into contact with him, not just in the past few years during his illness but in every day of his life. He lived a life as full as any human can live. Joy, abundance of spirit, infectious laughter. A titan of a ginger haired man."
Just two months before his death, Michael took to social media to inform friends, family and fans that he didn't have long left and that he wouldn't be going ahead with a tracheostomy which would have helped him to breathe.
He wrote: "Health update: Basically me and @nomsheehan were in hospital for over a week there - speaking to doctors and getting tests done etc. Talking about risks and implications of getting the trache put in. What day to day life would be like after the operation.
"In short I'm not going ahead with the tracheostomy.
"I had confirmation from it would be around 6-12 months before I could get home due to lack of staffing resources. Thanks so much to everyone who helped push this - from senior social workers, to politicians, to the chief executive of the hospital. Everyone has tried so hard, but there just isn't the staff."
He also spoke honestly about not wanting to spend his final moments suffering in hospital, with his quality of life likely to have been seriously impacted by the tracheostomy procedure.
Michael continued to act even after his diagnosis, earning an award for his portrayal of Richard III in a wheelchair during a Belfast play in 2024.
Michael added: "Also, my neurologist gave us the news that I likely have about one year left (obviously he can't say for definite and we still have hope for the drug trial to buy some more time too). So I don't want to risk a significant amount of that time being in a hospital bed.
"Thanks so much for all the donations to the GoFundMe, even though I didn't go ahead with the trachesotomy - it will still go towards providing me with specialist care as I enter the final stages of life. I'm still overwhelmed by all your generosity.
"Anyway - still lots to live for and lots planned - here's my wee godson Micheál visiting me in hospital."
Tributes have been flying in for the Northern Irishman since his death was confirmed, with SNL UK star George Fouracres describing him as 'one of the greatest human beings I ever shared my time with here on this planet'.
Rest in peace Michael.
Topics: Game of Thrones
