Randi Nordby started her career very early, and already as a child she was acting in Inga Bjørnson's children's theater.
She made her stage debut at age 12 in 1938 in The Women (Norwegian title: Kvinner) by Clare Boothe Luce at the New Theater in Oslo.
She made her adult debut in 1945 in Leonid Leonov's play Invasion at the Studio Theater, and she remained there until it had to close in 1950.
At the New Theater she appeared in plays such as William Shakespeare's Hamlet, Ralph Benatzky and Robert Stolz's The White Horse Inn (Norwegian title: Sommer i Tyrol), and Eugène Ionesco's The Chairs.
She was first married to the Danish theater personality and writer Kaare Trolle Bing (1921–2016),[5] and then to the Swedish film producer Eric Johnson[3] (died 1991).