Hann-Byrd made his film debut in 1991's Little Man Tate, directed by and also starring Jodie Foster. In 1995, he appeared as the young Alan in Jumanji at age 13, in which Robin Williams appeared as the adult version of the character. He has also appeared in films such as Diabolique (1996) and The Ice Storm (1997). In 1998, he appeared as Charlie Deveraux in Halloween H20: 20 Years Later and in 1999, in Uninvited.
Hann-Byrd was born in New York City, the son of Jacquie Hann, a children's book Illustrator and author, and Jeff Byrd, a television cameraman. In 2004, Hann-Byrd graduated from Wesleyan University in Connecticut with degrees in psychology and film studies.
In 2009, Hann-Byrd began working behind the camera after getting a job in the Writers room for the second and third seasons of the television show Fringe. In 2011, he spent a year as a fellow in the Warner Bros. Television Writers Workshop. Subsequently, Hann-Byrd served as a Writer for the Hulu series, The Morning After, and as a writer/producer for Participant Media's Brain Food Daily.
