By now, X-Men fans have devoured the critically acclaimed "X-Men: Days of Future Past," and a lot of theories surround the post-credit scene introducing Apocalypse.

As many fans know, "X-Men: Apocalypse" is slated to be the sequel to "X-Men: Days of Future Past," so the post credit scene is no surprise by any measure.

However, there is one theory regarding Apocalypse seen in the post credit scene, and that is he may in fact have been sprinkled throughout "Days of Future Past" without fans knowing.

In "Days of Future Past," a new mutant was introduced called Ink (real name Eric Gitter). He was seen in 1973 alongside Toad, Havoc, and another mutant soldier, about to be sent to Trask Industries for testing.

Ink is played by actor Gregg Lowe, and he can also be spotted early in the movie in the future timeline. You see him with a similar tattoo around his eye, being sent to a mutant concentration camp of sorts.

What's interesting about these two "X-Men: Days of Future Past" scenes is that Ink does not appear to age at all between 1973 and the future, which is presumably decades later.

In the post credit scene, we get a face shot of Apocalypse. It is interesting that the young Apocalypse looks strikingly similar to Ink.

On IMDB, Gregg Lowe is only credited as Ink, so this is unconfirmed, but could he have also portrayed the immortal Apocalypse?

Many X-Men fans already presume that "X-Men: Apocalypse" will have to explain why such a powerful mutant has been MIA from the conflicts of "First Class" and "Days of Future Past," but it may be possible that Apocalypse was quietly observing the action for his own purposes. However, by altering the timeline to a new path, perhaps the actions in 1973 will lead to Apocalypse surfacing in "X-Men: Apocalypse."

The only thing that does call this theory into question is that Ink's mutant ability may not match that of Apocalypse's (although he has many).

But what do you think? Do Ink and Apocalypse look to be played by the same actor?