[2] Koepp has achieved both critical and commercial success in a wide variety of genres: thriller, science fiction, comedy, action, drama, crime, superhero, horror, adventure, and fantasy.

Koepp has directed seven feature films over the course of his career: The Trigger Effect (1996), Stir of Echoes (1999), Secret Window (2004), Ghost Town (2008), Premium Rush (2012), Mortdecai (2015), and You Should Have Left (2020).

[4] While attending Kettle Moraine High School in Wales, Wisconsin, he worked evenings and weekends at the McDonald's restaurant in Delafield.

[7] As a writer, Koepp worked on blockbuster Hollywood films such as Jurassic Park with Steven Spielberg, Mission: Impossible with Brian De Palma and Spider-Man with Sam Raimi.

He had a cameo appearance as the "Unlucky Bastard", a minor character devoured by a T. rex roaming San Diego in The Lost World: Jurassic Park, which he co-wrote and was second unit director of.

He wrote the screenplay for Indiana Jones and the Kingdom of the Crystal Skull for Spielberg and George Lucas and co-wrote and directed 2008's Ghost Town starring Ricky Gervais and Greg Kinnear.

[19] On March 15, 2016, The Walt Disney Company announced a fifth installment of the Indiana Jones saga, with Koepp as its screenwriter and Spielberg directing again.

[28] On February 25, 2021, it was announced Koepp would write and co-produce the thriller Kimi, directed by Steven Soderbergh and starring Zoë Kravitz.