Greg’s debut as a feature director was with Transpecos, a thriller set within the United States Border Patrol. It premiered in competition at the 2016 SXSW Film Festival where it won the Audience Award. Transpecos was acquired by Samuel Goldwyn Films for theatrical release. He is also known for producingRising from Ashes, a documentary about the first Rwandan National Cycling Team and their 6-year journey to the Olympic Games in London. Executive Produced and Narrated by Forest Whitaker, Rising from Ashes had its World Premiere at the Hamptons International Film Festival and went on to 16 additional festival wins. Greg was a co-producer onGhost Fleet, a documentary about slavery in the Thai fishing industry which had its World Premiere at the 2018 Telluride Film Festival and International Premiere at the Toronto International Film Festival. Greg was a producer onRunning with Beto, a documentary following Beto O'Rourke's against-all-odds campaign for Senate premiered at SXSW 2019 winning the Audience Award and released by HBO. He served as co-writer / producer onJockey, which premiered at the 2021 Sundance Film Festival in the U.S. Dramatic Competition where it won the Special Jury Award for Best Actor and was acquired by Sony Pictures Classics for theatrical release. It went on to play at TIFF, AFI and over 30 other film festivals around the world. The film was nominated for the Indie Spirit Awards for best male lead and the John Cassavetes Award. Greg has spoken to thousands of students across the country and sat on panels about his work at esteemed venues such as SXSW, UNESCO, and the United Nations.

Sing Sing, his sophomore feature as a director, premiered at the 2023 Toronto International Film Festival in the Special Presentations program where it was acquired by A24 for a theatrical release. It had its US premiere at the 2024 SXSW Film Festival where it won the audience award in the Festival Favorites section.