[2] She first started learning to play the piano when she was three years old, and often spent evenings backstage at Stratford musicals with her parents.
[1][3] Growing up, Johnson was inspired to get involved in music and comedy after her father showed her videos of Victor Borge.
[1] She attended Stratford Central Secondary School, and received her Bachelor's degree in music composition from the University of Toronto.
[4] The musical, Big Box Story, was a comedy loosely inspired by Stratford's youth opposing corporate big-box stores taking over the small town.
Johnson and Sara Farb chose He Is Coming by Otto Willem Albertus Roelofs, which was performed in April 2016.
The musical was further developed with an expanded set and direction by Annie Tippe, when it was performed at the Goodman Theatre in Chicago between June and July 2022.
[10] The musical will return to Toronto, where it will play a limited engagement at the Ed Mirvish Theatre in April and May 2025.
[12] The musical, performed by Cullen and Johnson, is a comedy that focuses on the challenges and frustrations of growing up with dyslexia.
[13] In 2018, Johnson and her sister, Anika, co-created the immersive musical, Dr. Silver: A Celebration of Life.