He has an older sister named Lilly (born January 22, 1981) and three younger half-brothers from his father's marriage to Kelley Kuhr.

McDowell's next film, The Discovery, starred Rooney Mara, Jason Segel, and Robert Redford.

[15] In March 2017, filmmaker McDowell announced he was adapting author Don DeLillo's novel Zero K as a limited series for FX with Noah Hawley and Scott Rudin producing.

In 2019, McDowell directed the first and last episodes of the Showtime series On Becoming a God in Central Florida and also served as an executive producer.

His next film, Gilded Rage, was based on the infamous murder of investment banker Thomas Gilbert Sr. Bill Skarsgård and Christoph Waltz were set to portray the character in different periods of his life.