In tonight's episode of Agents of SHIELD, we're hoping to learn a lot more about the mysterious carving that Coulson has been doing, and maybe even get some answers. But one upcoming Marvel comic may already have a huge clue. Spoilers ahead... just posted an exclusive cover to an upcoming issue of The Inhumans, by artist Jose Ladronn:

And then they noticed the symbols on the floor, under everyone's feet — they sure look the same as Coulson's mysterious map. ComicBook's Jamie Lovett writes:

In the television series, the writing is leading both S.H.I.E.L.D. and Hydra to a secret, hidden city. The prevalent theory is that city is Attilan, home of the Inhumans, and this image certainly seems to strengthen the Inhumans connection.

Will we find out tonight? Now I'm twice as intrigued.