A 7th-dan black belt in Aikido, Seagal began his adult life as a martial arts instructor in Japan; becoming the first foreigner to operate an Aikido dojo in the country. He later moved to Los Angeles, California, where he worked as a martial arts instructor on Never Say Never Again; accidentally breaking actor Sean Connery's wrist during production. In 1988, Seagal made his acting debut in Above the Law. By 1991, he had starred in four successful films. He achieved further fame in 1992, when he played Navy SEALs counter-terrorist expert Casey Ryback in Under Siege.
However, On Deadly Ground (in 1994) and Under Siege 2: Dark Territory (in 1995) were less successful at the box office. During the latter half of the 1990s, Seagal starred in three more theatrical films and the direct-to-video film The Patriot. Since that time, with the exception of Exit Wounds (in 2001) and Half Past Dead (in 2002), his career has shifted almost entirely to direct-to-video productions. From 1998 to 2014, Seagal appeared in a total of 27 of these.
At the age of 58, he returned to prominence as Torrez in the 2010 film Machete; his first widely released film since 2002. Intermittently between 2009 and 2013, he filmed three seasons of his reality show Steven Seagal: Lawman, which depicted Seagal performing his duties as a reserve deputy sheriff in Jefferson Parish, Louisiana (season 1–2) and Maricopa County, Arizona (season 3). He also created and starred in two seasons of the undercover police drama series True Justice between 2011 and 2012.
Seagal is an accomplished guitarist; having released two studio albums (Songs from the Crystal Cave and Mojo Priest), and performed on a number of film scores. He has worked with many famous musicians, including Stevie Wonder and Tony Rebel (who both performed on his debut album).