Gruner joined Imperial Entertainment Corporation and began acting in action movies. In 1989, he starred in his first movie: the urban action movie
Angel Town. In 1992, Gruner starred as "Alex Raine" in
Albert Pyun's cyberpunk 1992 science fiction thriller
Nemesis. Both
Nemesis and
Angel Town were popular in video distribution, and
Nemesis is one of the movies Gruner is most proud of. In 2014, he featured as a director in
Sector 4: Extraction, a
direct-to-video release. In 2015, Gruner released one more film as a director, a producer, a screenwriter, and an actor:
EP/Executive Protection.
Film producing Early in his career, Gruner got involved in the production of some of the films in which he was appearing as an actor. This is the case for
Savage (1996),
Mercenary (1996),
Mercenary 2: Thick & Thin (1998),
Interceptor Force (1999),
The Circuit (2001), and
Crooked (2005). But it was only starting in the 2010s, except
Interceptor Force 2 in 2002, that he accumulated his involvement both as a producer, as an actor, and as a director in
One Night (2010),
Re-Generator (2011),
Sector 4: Extraction (2014), and
EP/Executive Protection (2015). He has also been involved, as a producer-only, in
Front Line (2015). He was both an actor and a producer in
Iron Cross: The Road to Normandy (2018).
Screenwriting Gruner co-wrote the stories of some of the movies in which he appeared as an actor. He wrote the stories of
T.N.T. (1997),
Interceptor Force 2 (2002),
Crooked (2005),
One Night (2010),
Re-Generator (2011), and
EP/Executive Protection (2015). He also co-wrote the story and the screenplay of
Lost Warrior: Left Behind (2008), and co-wrote the story of
Sector 4: Extraction (2014). == Business activities ==