Coombs was born and raised in Vancouver, Canada. He joined the school choir to better express himself and was soon cast in the role of Rum Tum Tugger in the musical play Cats. He rented a video of Elvis Presleyin concert to help prepare for the role.
He continued to do theatre roles throughout high school and eventually enrolled in the acting program at the University of British Columbia in Vancouver.
Coombs has appeared in productions at Bard on the Beach, an annual professional Shakespeare festival held in Vancouver; he has also appeared in the musical play A Little Night Music.