Casper is an accomplished actor, writer, film director and producer. A dual citizen of the United States and Sweden, he splits his time between the two countries. He currently has a couple of television series in different stages of development and is in the process of writing a screenplay that he plans to turn into a feature film. 

As an actor, Casper recently appeared in the Swedish crime movie "Beck - Ett nytt liv" as well as the drama series "Dolt under ytan" at Sveriges Television. Prior acting credits include guest-starring roles on TV shows like "Hawaii Five-0," "Deadbeat" and"Swedish Dicks." Co-starring credits include "The Blacklist" and "Lethal Weapon." His many film roles include the Academy Award-winning "Little Children," On stage, Casper has played both Hamlet in "Hamlet" and Romeo in "Romeo & Juliet."

Casper runs the independent film production company Embrem Entertainment. In 2020, he was nominated for the John Cassavetes Award at the Spirit Awards for producing Wild Nights with EmilyMadeleine Olnek's comedic biopic about Emily Dickinson starring Molly Shannon. Also in 2020, Casper premiered his 10th feature film as a producer, when the Swedish relationship drama Are We Lost Forever, directed by David Färdmar, had its world premiere at the Gothenburg International Film Festival. The film has been sold for distribution in 12 countries. 

In the US Casper directed eight multi-award winning feature films (five of which he also wrote): "Slutty Summer" (2004), "A Four Letter Word" (2007), "Between Love & Goodbye" (2008), "The Big Gay Musical" (2009), "Violet Tendencies" (2010), "Going Down in LA-LA Land" (2011)"Kiss Me Kill Me" (2015) and "Flatbush Luck" (2016). He has also written and directed "Ett Sista Farväl" ("A Last Farewell") (2013) in Sweden. The short film went on to play over 130 film festivals worldwide and picking up eighteen awards. 

Casper has been selected as one of the 100 most influential and newsworthy LGBT people by Out Magazine.