After graduating from the University of Toronto with a Bachelor of Arts degree in Sociology in 1948, he worked variously in construction, at the Canadian National Exhibition, made an independent film with a classmate and acted in summerstock theatre.

[4] Yost auditioned and, through the 1960s, appeared intermittently on the CBC as a panelist on shows such as Live a Borrowed Life, The Superior Sex and Flashback.

In the mid-1960s, he created and hosted CBC's Passport to Adventure, featuring classic movie serials, and also assisted in the founding of the Metropolitan Educational Television Authority (META).

As the show grew in popularity, funds were found to send Yost and a crew to Hollywood to arrange interviews with film personalities.

The library includes interviews with the stars of classic films, character actors, directors, screenwriters, composers, film-editors, special-effects people, and sometimes even their children.

Yost wrote four books: Magic Moments from the Movies, Secret of the Lost Empire, Billy and the Bubbleship (also known as Mad Queen of Mordra) and White Shadows[3] the latter being a mystery novel, published in 2003.