He spent much of his early career working in theatre, notably at the Abbey Theatre in Dublin. After playing Michael Evans in the original West End and Broadway productions of Brian Friel's play Dancing at Lughnasa in the early 1990s, McSorely started to attract more TV and movie roles. He has appeared in many Hollywood movies including Braveheart (in which his character was decapitated) and In the Name of the Father. One of his most celebrated performances was his lead role in Omagh, a feature-length television drama depicting the effect of the Omagh bombing on the residents of the town. He is also known for playing "Father Todd Unctous" in an episode of the Channel 4 sitcom Father Ted. His film credits include The Constant Gardener, and he was also cast as Queenan in The Departed but had to pull out (Martin Sheen took over the role). McSorley most recently played the role of Robert Aske in the Showtime historical drama The Tudors. He is currently filming the movie Robin Hood, directed by Ridley Scott and also starring Russell Crowe.