This year's Avengers: Endgame brought the MCU to a temporary close, taking us back through the decade-long cinematic universe and bringing several character's stories to an end. However, despite being a conclusion of sorts, the film still left many unanswered mysteries, with the age of the perpetually young Captain America being one of them. Well, now we have an answer to this age-old (get it?) question courtesy of Avengers: Endgame's visual effects producer Jen Underdahl.

Underdahl spoke recently about the different elements of Avengers: Endgame, as well as Avengers: Infinity War, and one thing she discussed was the task of aging up Captain America for the film's finale. She goes on to explain that in order to get the look they wanted, there were certain questions that needed to be asked, one of them being 'what Steve Rogers would look like at the age of 106'.

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"What would a super soldier look like if he had aged 106 years? What would his skin look like?"

To achieve this effect of aging-up (rather than de-aging as is the usual Marvel modus operandi), once they had decided on the number 106, the team began casting for an older actor on which to base the skin, a skin-double to give them their official title. Incidentally, the actor that took that much-coveted title arguably looks more like an aged Captain America than Chris Evans.

She then goes on to explain that the look was further crafted by shrinking and reducing Chris Evans' neck, shoulders and profile in order to take the character out of his prime and into super old age. This was achieved using a similar technique to that which was used in 2011's Captain America: The First Avenger whereby they warped Evans' body to shrink it down and thus achieve his pre-super-soldier-serum skinny frame. Though, Underdahl does point out that this was done with a much less heavy hand for the old Captain America.

The question remains, how did the visual effects wizard and her team land on the number '106'? Well, we can make this logical conclusion using the things we already know about the super-soldier superhero. Quite simply, they more than likely used his birthday.

Born on 4th July 1918, because of course he was, that would make Steve Rogers between 105 and 106 in 2023, the year in which the majority of Avengers: Endgame is based. Of course, for several decades he was frozen in ice after crashing down during World War I, but let's try not being sticklers for a change.

Whether aged Cap will be the end of the character in the MCU remains to be seen, with many speculating that we could be treated to further adventures as he navigates his way through time returning the Infinity Stones to their rightful place. For now, Sam Wilson's The Falcon holds the shield and the mantle, whilst Cap is busy playing shuffleboard. This news comes from Wired Youtube.