[3] He gained his first credit as a documentarian at the age of 17, when he and a friend directed a film titled The Pocket, about D.C go-go music.

[8] While still in his senior year at Georgetown, Cahill began interning with National Geographic Television and Film, soon becoming their youngest field producer, editor and cinematographer.

There he was taken on as editor for two Sundance features, Leonard Cohen: I'm Your Man and Everyone Stares: The Police Inside Out.

[9] Variety reported: "[It] has been deemed one of the more highly praised pics of the fest as it received a standing ovation after the screening and strong word of mouth from buyers and festgoers."

[14] Starting in 2015, Cahill is an executive producer of the Syfy TV show The Magicians, and directed the pilot episode.

[15] He considers Krzysztof Kieslowski one of his favorite filmmakers, specifically citing The Double Life of Véronique as having a profound impact on him.