His breakthrough role was that of aspiring Navy pilot Sid Worley in An Officer and a Gentleman (1982), for which he was nominated for a Golden Globe Award.

Keith had supporting roles in features including Major League II (1994), The Indian in the Cupboard (1995), U-571 (2000), Men of Honor (2000), Behind Enemy Lines (2001), and Daredevil (2003).

Keith played a local thug in The Great Santini, starred in The Lords of Discipline and White of the Eye, and held a prominent supporting role in U-571 opposite Matthew McConaughey.

He appeared in Ernest Goes to School as Squint Westwood (a spoof of Clint Eastwood) and in The Indian in the Cupboard as the cowboy "Boo-Hoo" Boone.

[6] Keith was present during the sentencing phase for John Couey, who was convicted of kidnapping, raping, and murdering Jessica Lunsford.

[citation needed] Keith said that he was planning on going to Washington, D.C., with Mark Lunsford after the sentencing, to lobby Congress for more support of sex offender laws.