"Do you feel protective over it now?" Alison asked. "If you know it's going to carry on without you, do you feel protective over how they're going to do it?"
"Well, I don't know to be honest," Douglas replied. "I try not to think about it too much.
"I think, well, I love what we all did together, and I'm very happy with that.
"I mean, it's going to be a different show now. So, I mean, I wish them all every success, but I don't know that I'll be able to watch it."
Shetland expected to return to BBC One in 2023.
