Alex O'Loughlin (born Alexander O'Lachlan) is an Australian actor, currently starring in CBS's Hawaii Five-0 as Lieutenant Commander Steve McGarrett. He previously had starring roles in the films Oyster Farmer (2004) and The Back-up Plan (2010), as well as the 2008 TV series Moonlight and the 2009 TV series Three Rivers. He is also known for a several-episode appearance as Kevin Hiattin the TV series The Shield.
O'Loughlin was born as Alexander O'Lachlan in Sydney, Australia, of Irish and Scottish descent. He was educated at Macquarie Primary School, where his younger sister Jennifer also studied. His year of birth has been given, variously, as 1974, 1975, and 1978. His father is a physics and astronomy teacher in Sydney and his mother is a nurse.
O'Loughlin suffered from asthma, attention deficit hyperactivity disorder (ADHD or ADD) and obsessive compulsive disorder (OCD) when he was a boy. He wanted to become a jet fighter pilot but was told by his teacher that it was unlikely due to his asthma. This was a painful memory for him that recently evoked the response, "Always teach children to reach for the stars." He was a fan of heavy metal music and the Japanese TV series Monkey.
Playing dress up with items out of an old trunk was one of his favorite pastimes. School was a continuous struggle, caused by learning difficulties that were compounded by ADHD and OCD, and he left when he was 14, after which he held jobs in a wide range of fields. He enrolled at the National Institute of Dramatic Art (NIDA) in Sydney, Australia, in 1999. Despite a challenging first year, he graduated from NIDA in June 2002, after completing a 3-year, full-time Bachelor of Dramatic Art program.
O'Loughlin was already working in short film and fringe theater as a teenager in Sydney. One of the first acting jobs he recalls is being an extra in a commercial, playing a marine. After graduating from NIDA, he began his career in Australian television and film productions and some of his TV credits include roles in BlackJack: Sweet Science, Love Bytes and White Collar Blue.
His film career started off in 2004 when he landed his first lead role in Oyster Farmer. He later appeared in Man-Thing, Feed, and in the Australian mini-series The Incredible Journey of Mary Bryant, for which he received a nomination as the Best Lead Actor in Television from the Australian Film Institute Awards in 2005 and as Most Outstanding Actor in a Drama Series from the Logie Awards in 2006.
O'Loughlin's first son, Saxon, was born in July 1997 to a girlfriend with whom he has since separated.
He separated from his long-time girlfriend, Australian actress/singer Holly Valance in February 2009.
Another son, Lion, was born in October 2012 by his girlfriend, model/surfer Malia Jones.
O'Loughlin lives in West Hollywood, California, but while filming Hawaii Five-0 he lives in Hawaii.