Auditioned for the role of Batman in Batman Begins (2005). The role was eventually given to Christian Bale. But director Christopher Nolan liked Cillian's audition so much that he gave him a role as Batman's arch- nemesis Jonathan Crane/Scarecrow, who is a developing character in this movie.

Though he did not get the role of Batman in Batman Begins (2005), he did get to wear the batsuit during an audition with Christopher Nolan.

He used to play in a Frank Zappa-influenced band called 'Sons of Mr. Greengenes' with his brother.

As of 2006 he is the most nominated Irish Actor at the Irish Film and Television Awards with 6 nominations.

Played two psychopaths in 2005: Dr. Jonathan Crane (Scarecrow) in Batman Begins (2005) and Jackson Rippner in Red Eye (2005).

Son Malachy was born December 4th, 2005, weighing 7 pounds and 5 ounces

Has two sisters, Sile and Orla.

First name pronounced "Kill-ian".

Father is a school inspector.

He schooled at Presentation Brothers College Cork.

He was planning a career in law until he discovered the world of acting.

Proposed to wife while hill-walking in Ireland.

Lives in London, England.

He greatly admires actor Liam Neeson. Looks at him as a surrogate movie dad.

Is fluent in French and Irish.

Although he is a vegetarian, he learned to chop up meat in an abattoir for his role as butcher in Girl with a Pearl Earring (2003).

Has a younger brother, Páidi, a design engineer.

His father is a school inspector and his mother is a French teacher.

He was the oldest of four children.