Warning: Full spoilers follow for Godzilla: King of the Monsters.
With the release of director Michael Dougherty’s Godzilla: King of the Monsters, newcomers to the classic franchise are being introduced to three characters — well, monsters — from the original Toho series that are near and dear to most fan’s hearts: King Ghidorah, Rodan, and the Queen of the Monsters, Mothra.
And it’s the latter creature — a giant moth who is a friend to Godzilla and helps him in his battle with the nasty Rodan and the three-headed space dragon Ghidorah — who winds up leading to the biggest Easter egg in the film. Because not only do we get Mothra herself, but the film also hints at the existence of the “Mothra twins.” The who?!
Source: IGN.com Godzilla: King of the Monsters' Craziest Reference