Marvel Cinematic Universe: Definitive Guide To Easter Eggs, In-Jokes And Foreshadowing

Thor

7. Selvig Finds A Drawing Of Odin Holding The Tesseract

When Selvig's researching Asgardian myth, he comes across a children's book that features some pretty cool Easter eggs. On top of showing the Bifrost as the more typical rainbow bridge from the comics, it features Odin wielding the Tesseract, the second drawing of the Infinity Stone ahead of its introduction later in this film.

6. Hawkeye

When Thor breaks into the S.H.I.E.L.D. camp to reclaim his hammer, the man called upon to take him out is none other than Clint Barton, in a brief cameo designed to establish Hawkeye ahead of The Avengers. It's the most slight set-up of any of the team, sadly setting a precedent for Hawkeye to be one of the more under-utilised heroes.

5. Donald Blake Pseudonym

In the comics, Thor has a proper, human alter ego (created by Odin, but still), known as Donald Blake. That doesn't really fit the mask-less heroes of the MCU, so that part of the character was ejected, but there are still nods to Blake. He's set up as Jane's doctor ex-boyfriend and the name is later used as a cover when Selvig tries to break Thor out of S.H.I.E.L.D. captivity.