Marvel Studios' latest, Thor: Ragnarok, is loaded with gags spoken and visual, and the result is an adventure that's easily the God of Thunder's best to date on the big screen. Among its many laughs is a particular scene featuring three major cameos.

Warning: Spoilers for Thor: The Dark World and early spoilers for Thor: Ragnarok follow. If you're yet to see the film, don't read on; one of the cameos is completely unexpected and best left as a surprise.

In Chris Hemsworth's last solo outing as Thor, Tom Hiddleston's Loki faked his own death to claim Asgard's throne from his father Odin (Anthony Hopkins).

Disguising himself as Odin and banishing the real one to Earth, Loki spent the next two years letting Asgard and the nine realms under his protection descend into chaos as he pampered himself.

When Thor returns to Asgard, he finds Loki as Odin feeding himself grapes and enjoying some public theatre, in particular a play about Loki's "death" that celebrates him as the hero he's never been.

Thor quickly figures out the truth, but first we get to see the play in action. It's here we get those three big cameos.

Sam Neill - who starred in Ragnarok director Taika Waititi's previous film Hunt for the Wilderpeople - appears as the narrator, but the actor's role in the film was revealed some time ago, during production.

Then there's the Asgardian playing the role of Thor, who is none other than Luke Hemsworth - Chris Hemsworth's own brother - best known for his role in HBO series Westworld. The other Hemsworth - Liam - does not appear. At least, we didn't spot him if he did.

The third cameo is undoubtedly the biggest, and was somehow kept completely under wraps. Matt Damon - yes, Oscar-winning star of Good Will Hunting and The Martian Matt Damon - plays another Asgardian actor hamming it up as Loki, complete with long black hair and familiar green outfit.

Of course, there's a Stan Lee cameo as well later on. So don't worry about that. The Marvel legend appears around the halfway point of the film and is the one responsible for giving Thor his new, shorter haircut ahead of his gladiatorial battle with Mark Ruffalo's Hulk.

Damon's appearance is perhaps the best cameo in the Marvel Cinematic Universe to date not made by a recurring character or Stan Lee. Previously we've seen the like of Samuel L Jackson's Nick Fury, Robert Downey Jr as Tony Stark and Ruffalo and Hemsworth in their roles appear in credits scenes for other outings.

Hemsworth appeared in an end credits scene for Doctor Strange, a scene that plays out in this film after the Damon cameo with Thor looking for Odin and getting help from Benedict Cumberbatch as Strange.

The cameo makes a bit more sense of Damon's recent appearance on US talk show Jimmy Kimmel Live, where he "crashed" an interview with Hemsworth, Waititi and Ruffalo.