His family returned to England in 1933 and three years later he became an admirer of documentaries after seeing the 1936 film Night Mail, which was narrated by John Grierson (the founder of the NFB) and based on a poem by W.H.

Macartney-Filgate was only 15 years old at the outbreak of World War II and ultimately joined the Royal Air Force as a flight engineer, flying more than a dozen operations in Europe.

[2] Macartney-Filgate worked the NFB's Unit B, with such filmmakers as Wolf Koenig, Roman Kroitor, Stanley Jackson, Michel Brault, and Pierre Perrault, all of whom were at the forefront of the new unscripted, observational documentaries.

Executive producer Tom Daly oversaw the filmmakers, and the shorts were shot on location using new lightweight equipment with an emphasis on recording everyday life.

The film, Robert Frost: A Lover's Quarrel with the World (1963), went on to win the Academy Award for Best Documentary Feature, with Clarke credited as the sole director, despite Macartney-Filgate directing the majority of it.

In New York City, he worked with William Greaves, who he had previously collaborated with on the Candid Eye series, and made films for television about such writers as Harold Pinter, Marshall McLuhan and Henry David Thoreau.

He returned to Canada in the late sixties and again rejoined the NFB briefly to work on the Challenge for Change series, before moving to the Canadian Broadcasting Corporation.

[4] At the CBC, he directed the Lucy Maud Montgomery: The Road to Green Gables (1975), Grenfell of Labrador: The Great Adventure (1977), and Fields of Endless Day (1978).