MARC O'Shea, "a talented actor, a best friend and a good soul" best known for the acclaimed TV drama `You, Me and Marley', has died suddenly.
Raised in the lower Omeau Road area of Belfast, Mr O'Shea had been living in Annsborough, close to Castlewellan, Co Down.
Mr O'Shea, who was in his early forties, was found dead on Saturday and it is understood that a crime is not suspected.
His impressive acting career included several high-profile roles, including appearing as loyalist paramilitary leader Johnny Adair in Channel Four biopic `Mo'.
He also worked alongside Peaky Blinders' star Cillian Murphy in the film `Breakfast on Pluto' and Bronagh Gallagher in `You, Me and Marley'.
In local theatre he was production manager for Brassneck's popular comedy `A Night With George' and part of the productions `Black Taxis' and `The Session' with Dubbeljoint and `The Chronicles of Long Kesh' with Green Shoot.
Mr O'Shea was also known for his dedication to social justice issues, with one friend observing he was "totally committed to fighting all forms of discrimination and oppression, an inspiration to all around him".
In the final post on his Facebook page, he was urging people to support the Parity Of Mind Campaign's petition for "a new modern mental health hospital in Northern Ireland."
"As someone that suffers with mental health issues I think it's disgusting how the Tories and their cronies are destroying what little mental health care there is left," he told his followers.
Friends and colleagues have been paying tribute.
Producer and director Stephen Beggs said "the theatre community in Northern Ireland is having to come to terms with the sudden death of yet another of our friends and colleagues, Marc O'Shea".
"Marc was a fine actor and a great friend to many of our members. He will be much missed by everyone who knew and worked with him," he said.
Kabosh Theatre Company said it was "very sorry to hear of the sudden death of actor Marc O’Shea".
"We had some craic working with him on the Referee project for the Electoral Commission in Belfast and Derry. He'll be sorely missed. Rest easy."
Dudi Appleton, who directed Mr O'Shea in `The Most Fertile Man in Ireland', described him as "a viciously talented actor and a huge heart".
"He was the soul of the set any time I saw him work," he said.
"We were shooting one day in Ardmore and I saw Marc in the costume truck. I was pretty sure he wasn't called that day. Turned out he showed up because it was no fun in the hotel on his own.
"He came onto set in a blue camisole, wig and makeup and announced he was Tara Lynne O’Neill’s body double. Hard not to cry thinking about the times Marc kept us laughing.
"God bless you (wee) big man."
Centre Stage Summer Drama Holiday organisers described him as "one of our own, a truly talented actor, a best friend and a good soul".
"We are devastated and in complete shock."
His funeral will be in Our Lady Of The Assumption Church, Newcastle, with Requiem mass at 10am on Wednesday with burial afterwards in St. Patrick's Cemetery Bryansford.
He is survived by his mother Moira and siblings Danielle, Joe and Michael.
