Brolly was born in Belfast, Northern Ireland, the son of Clark Brolly (1930-2014), a salesman, and Rosemary Brolly. He is the third of four siblings, he has two brothers: Clark and Michael 1968-2006, and one sister, Cathy. Growing up in Belfast in a mixed religion home was difficult for the young Brolly. His mother was a Catholic and father a Protestant, while there was a sectarian war going on between the two faiths. Tired of the mindless violence, Shane left Belfast at age fifteen and moved to London. After working odd jobs, he saved enough to come to Los Angeles. While attending The Valley College, Shane ran into some theater students who suggested he sign up for their class. Soon thereafter he was cast as an Irish cop in the play:"Wait until Dark" at the college's Horse Shoe Theater. Shane landed his first role as Jack in the Movie "Flypaper." Beside acting, Brolly is a published author. His first book, "You'd Think There Would Be More Suicides Around Here," was critically acclaimed.