Prior to winning the role on Stranger Things, Harbour appeared in small roles in films including Brokeback Mountain, Quantum of Solace and The Green Hornet.
The fourth season of Stranger Things is currently in production, having been delayed earlier this year due to the coronavirus pandemic.
Harbour is set to return as Hopper, even though his character was seemingly killed off at the end of Stranger Things’s third season.
“I had gotten to a place in Hollywood where I was playing fifth and sixth on the call sheet,” he added.