Joss Whedon reveals in his dependably witty commentary on the Blu-ray release of  Avengers: Age Of Ultron (out to buy in the UK from 14 September)  that he managed to sneak a Buffyverse Easter egg into the Marvel film so clever, so ingenious and so subtle that if you ever meet any one who reckons that they spotted it at the cinema, then point at them in a crowd and shout, “Liar, liar, pants on fire!” very loudly.

Remember Angel, the spin-off from Buffy The Vampire Slayer in which her bloodsucking ex -boyfriend decamped to Los Angelese to set up a supernatural detective agency? Remember the legal firm that began as Team Angel’s nemesis but which they ended up reluctantly running by the final season? Remember what it was called? Wolfram & Hart.

Well, in Thor’s weird trippy dream vision sequence, there’s a brief glimpse of three shoadowy figure in some archways. They’re wearing masks. And guess what the masks represent?

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