Born in Douglas, County Cork, Ireland, Murphy was raised by schoolteacher parents; his father, Brendan, worked for the Irish Department of Education, and his mother taught French. Despite the focus on education, Murphy's first passion was music. He formed a band with his younger brother called the Sons of Mr. Green Genes - a tribute to their musical idol Frank Zappa - which Murphy once described in The New York Times as being "very much like 20-year-olds showing off how proficient they were with their instruments." Much to the relief of his parents, he dropped his musical ambitions to study law at University College Cork. His interest in law waned a year and a half later, leading Murphy to drift elsewhere, namely the Corcadorca Theater Company, a local theater where he began lobbying the director to cast him in "Disco Pigs." Murphy won the part, while the play opened to rave reviews and remained a European staple throughout the years. It was then turned into a film in 2001 by Kirsten Sheridan, daughter of famed Irish director Jim Sheridan. Murphy reprised his role onscreen, but reviews were not as glowing for the film as for the play.Eighteen months of touring with "Disco Pigs" led Murphy to an Irish rendition of "Much Ado About Nothing," one of the only Shakespeare productions in the young thespian's career. Meanwhile, he made his film debut in "The Trench" (1999), a dramatization about the lead-up to the Battle of the Somme during World War I, in which his character was blown to bits in the first 30 minutes of the film. Murphy next appeared in "Sunburn" (1999), playing a slacker vacationing on Long Island whose reckless behavior forces him to reevaluate his life and the troubles that await him back in Ireland. After a supporting role in the Irish-produced "Catch the Sun" (2000), Murphy played the abused son of a Depression-era father (Colm Meaney) hell-bent on ruining the life of a local Irish businessman (Adrian Dunbar) in "Bitter Harvest" (2001). Murphy then had his big break in "28 Days Later" (2002), Danny Boyle's sci-fi horror feature about a virus that drives people into a homicidal rage and nearly wipes out all of England. Frightening in its all-too-realistic depiction, "28 Days Later" was the surprise hit of the summer and the most talked about movie of the year.Thanks to the exposure from "28 Days Later," Murphy was offered bigger and better roles, including playing a peasant boy who romances a young girl (Scarlett Johansson) who is the subject of Johannes Vermeer's (Colin Firth) famous painting in "The Girl With the Pearl Earring" (2003). After playing a deserting soldier in "Cold Mountain" (2003), he appeared in "Intermission" (2004) as a sorry sod whose trial breakup with his girlfriend (Kelly MacDonald) leads him to eagerly participate in a disastrous robbery attempt. Meanwhile, his theater career continued unabated with a turn as the emotionally fragile Konstantin in Anton Chekhov's "The Seagull," staged at King's Theatre in Edinburgh. Murphy was propelled into the limelight after appearing as Dr. Jonathan Crane (a.k.a. Scarecrow) in Christopher Nolan's excellent reboot, "Batman Begins" (2005). Murphy, who was at one point considered to play Batman/Bruce Wayne over Christian Bale, turned in an appropriately creepy and magnetic turn as the fearsome Dr. Jonathan Crane/Scarecrow, adding a touch of much-needed zaniness to the serious proceedings.Murphy quickly followed up with the Wes Craven-directed thriller, "Red Eye" (2005), playing the not-so-subtly named Jackson Ripner, a mysterious man who menaces a resourceful hotel employee (Rachel McAdams) during a red-eye flight. He next returned to Ireland to star in Neil Jordan's "Breakfast on Pluto" (2005), playing transvestite Patrick "Kitten" Braden, an aspiring model-turned-prostitute and IRA bomber. Murphy stuck around his native Ireland during summer 2005 to film "The Wind That Shakes the Barley," a period drama set during the Irish Civil War in 1919 in which he played one of two brothers who join the guerillas to fight the British Black and Tan squads trying to prevent their country from gaining independence.Reuniting with "28 Days Later" director Boyle, Murphy was part of the ensemble cast of "Sunshine" (2007), a sci-fi thriller about a crew sent into space to save the dying sun with a special device, only to lose contact with the Earth and their own sanity. Following a cameo appearance as the Scarecrow in the opening minutes of "The Dark Knight" (2008), he co-starred in the period drama "The Edge of Love" (2009). After co-starring in "Perrier's Bounty" (2010), a comedic thriller about three fugitives on the run from a big time gangster, Murphy reunited with Christopher Nolan for "Inception" (2010), a contemporary sci-fi thriller about a corporation that has developed technology to enter dreams and extract information from the human mind. Following the British horror film "Retreat" (2011) and science fiction thriller "In Time" (2011), Murphy starred in Spanish-American drama "Red Lights" (2012) and coming of age drama "Broken" (2012) before concluding the Scarecrow arc in "The Dark Knight Rises" (2012). Starring roles opposite Jennifer Connelly in the drama "Aloft" (2014) and Johnny Depp in dystopian science fiction thriller "Transcendence" (2014) were followed by a key role in Ron Howard's whaling ship drama "In the Heart of the Sea" (2015). Starring roles in World War II espionage drama "Anthropoid" (2016) and action comedy "Free Fire" (2016) followed, before Murphy starred in Sally Potter's comedy "The Party" and appeared in a small role in Nolan's World War II battle film "Dunkirk" (2017).