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These days, it almost feels like you need to have some sort of advanced degree in Easter Egg hiding to qualify to make comic book movies. The currency of references, hidden in-jokes and secrets has swollen to the point where actually watching films for their entertainment value occasionally takes a back-seat to combing through them for signs that the directors love the source material as much as the fanboy audience.

That counts almost doubly for the current crop of DC movies, for which Zack Snyder seems to have made it an over-arching manifesto to stuff in as many secrets and Easter Eggs as possible, to bait fans and encourage them to talk about the films as detailed master-pieces for years after release. It's a clever little tactic, and there really is no getting past the fact that the attention to detail in there is astounding.

But it's also not entirely new, of course: ever since Superman flew into cinemas at the tail end of the 1970s, funny book movies have been stuffed with Easter Eggs on a sliding scale of obscurity, some of which took years to even notice. And the creators behind those secrets deserve serious celebration for their fiendish intellect.

Here are the 21 greatest obscure Easter Eggs hidden in DC movies...

21. The Superman Shout Out - Batman v Superman

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It was incredibly to miss the first time out - or first several times, actually - but as eagle-eyed fans have spotted, in the sequence that shows accidental terrorist Walter Keefe's "shrine" to Superman in BvS, one of the headlines reads “Superman Shifts Tectonic Plate; Prevents Devastating Earthquake.”

That would be the self-same earthquake that killed Lois Lane in the first Superman movie (until Superman "fixed it").

Keefe's creepy wall also includes a poster recapturing the iconic image of the cover of Action Comics No 1 (which has also appared in Superman and Man Of Steel)...

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