David Harbour has compared Hopper to Galdalf the White.

The 'Stranger Things' star has teased his character's involvement in the highly anticipated fourth season of the Netflix sci-fi show, and he compared his alter ego to the literary wizard's resurrection in the 'Lord of the Rings' trilogy.

Referring to Hopper's daughter Sarah, he told Deadline: ''I've always sort of hung onto this idea that the only way to reconnect with that Sarah character, and the fact that the only villain in a sense was Hopper, because she had cancer.

''There was no bad guy.

''I've always felt that he, in some sense, had to die, so I think they've crafted something really beautiful where in a sense he does sacrifice himself, and as we've seen from the teaser, he's resurrected, almost in my mind, like a Gandalf the White.''

Production for the upcoming series had to be halted due to the coronavirus pandemic, and there's currently no word on how or when filming can resume.

However David, 45, has opened up about what fans can expect from the new season, and he teased a ''darker palette'' for Hopper.

He added: ''Hopper is the American in that Russian prison, and to me, what happens in this season--first of all it's very epic and very big in a 'Stranger Things' way.

''There's monsters, there's horrors, there's scares, there's also like great 'Indiana Jones'-type action, but also we get to see some of Hopper's really deep backstory that we've hinted at with the boxes in season two, and I'm really excited to let people see these really deep colours in him.

''Each season we see a different side of him, and last season he was sort of wacky... now I think he's painted in a bit of a darker palette and he's able to express some of these really deep things in him, which we haven't really known yet.

''It's been hinted at, but we don't really know.''