Put on your Science Bro thinking caps and solve this puzzle. It may be a title clue for "Avengers 4." It also may not. Those are the options!

Directors Anthony Russo and Joe Russo are hard at work on "Avengers 4" -- but also opening a new restaurant, see below -- and shared a new mystery with fans.

We just got a look at the first "Captain Marvel" trailer, and next up Marvel should be giving us the official title for "Avengers 4." It's possible we'll also get the first trailer in the next couple of months.

The Russos just teased fans with a black-and-white set photo, suggesting we "Look hard..." for clues:

Some fans spotted four As for "Avengers 4," among other things:

That "End Game" might be a slight stretch, but we love it anyway. End Game for the win. One word or two, though?

You may have also noticed that Joe Russo is now co-owner of a restaurant in downtown Los Angeles, and he worked his Rolodex to get several MCU stars in early, before this Thursday's grand opening:

Chris Evans has his clean-shaven look, which matches his classic Captain America "Avengers 4" photo from the other day.

All of this should put a smile on your face, which may or may not end in tears when "Avengers 4" premieres next May.

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