Higgins' father enlisted in the army following the attack on Pearl Harbor, and his mother returned to her home in Sydney with Colin and his elder brother.

Apart from a brief stint in San Francisco in 1945, Higgins lived in Sydney until 1957, mostly in the suburb of Hunters Hill, attending school at Saint Ignatius' College, Riverview.

After moving to Redwood City, California, Higgins attended Stanford University for a year, but then lost his scholarship because he became "obsessed" with theatre.

Higgins was discharged in 1965, spent six months in Europe, mostly in Paris, then returned to Stanford University to study a Bachelor of Arts in Creative Writing.

"[5] While at college Higgins supported himself as an actor, playing in small theatre productions, including acting in a sex farce called Once Over Nightly for a year and a half.

He began working on a Master of Fine Arts in screenwriting at UCLA, where his classmates included Paul Schrader and actor brother Barry Higgins.

[7][8] After graduating he went to work for a wealthy family in Los Angeles as a part-time chauffeur and pool cleaner in exchange for free accommodation, where he met film producer Ed Lewis.

Higgins wanted to direct the script himself and was allowed to shoot a director's test for $7,000 but Paramount was not sufficiently impressed, and Hal Ashby was hired.

[10] He then received an offer from Jean-Louis Barrault in Paris to turn Harold and Maude into a play for French actor Madeleine Renaud.