Stefan is best known for his role as Barry Lockridge in the Irwin Allen series Land of the Giants. Stefan has also starred in several movies including "The Way West" with Richard Widmark and Robert Mitchum, "Class of 1984", "Fear No Evil", "Strange Days", "The Final Cut", and the 2005 version of "The Fog".
Before landing the co-starring gig in Land of the Giants, Stefan had guest roles on the small screen in the likes of The Defenders, Gunsmoke, T.H.E. Cat, Combat, Dragnet and The Virginian. Later on, roles in Switch, Police Story and TJ Hooker would cement his television credentials.
In recent years has appeared in the likes of Highlander ("Courage"), The Sentinel ("Payback"), The X Files ("Terma" and "Tunguska"), Poltergeist: The Legacy ("Ransom"), Viper ("Stormwatch"), Millennium ("Thirteen Years Later" and "Goodbye Chris"), The Crow: Stairway To Heaven ("The Road Not Taken"), 7 Days ("The Dunwych Madness"), Special Unit 2 ("The Eye"), UC: Undercover ("The Seige"), Cold Squad ("True Believers"), Da Vinci's Inquest ("Wash The Blood Out of The Ring" and "Dizzy Looking Down") and Dead Like Me (the pilot episode). He also appeared as Shire Reeve in "The Legend of Earthsea" mini-series.
Stefan is a very accomplished musician. He had a band called "The Knights of The Living Dead", in Los Angeles from 1986 to 1993. The band was offered several deals, and signed with Capitol Records. Unfortunately, the president of Capitol was fired that same week, and the new president dropped all the new bands that were signed but had not gone into the recording studio.
The band did get money to make a demo with Dave Jerden (Jane's addiction, Rolling Stones, etc) as producer. But by the time everything was done, the band was breaking up. Stefan and his partner Roland Devoile continued to make music until the 1994 Northridge earthquake, when his girlfriend, now wife, Dawn, decided it was time to leave Los Angeles. They moved to Vancouver, Canada later in 1994.
Stefan also helped his sister (Alison Arngrim) get one of her first roles on the series Room 222, who went on to fame as Nellie in Little House on the Prairie.
Stefan won The Science Fiction Film & Fantasy Award "Best actor" for "Fear No Evil" in 1981, and was recently Nominated for a Gemini Award in the category "Best supporting actor" for "The Life" in 2005. The movie production of The A Team brought Stefan back to the big screen. Most recently Stefan has had a recurring role in the hugely popular television series Fringe.
Stefan has several projects on the go at the moment including his own production called The Last Ride with writing partner Anthony Wilson. He is also working on a number of music projects with a new CD in the works. To top all of this, Stefan recently met up with his fellow Land of the Giants cast members to record a quite unique audio soundtrack commentary for the UK Land of the Giants Season 2 DVD release.