12 Past MCU Easter Eggs That Will Mean Something In Phase 4

8. "I Have Red In My Ledger"

The Easter Egg

Right back when she first came together with the other Avengers, Black Widow vaguely mentioned wanting to atone for the "red in her ledger." It was never clarified, but it was a nod back to the comics backstory for Widow that had her playing the role of villain before her defection to the good guys.

How It Will Come Back

We're probably going to find out exactly what that red is thanks to the long-whispered-about and now finally confirmed Black Widow stand-alone.

There's no way that will be a sequel with that much mysterious story in Natasha's pre-Avengers life, and the smart money would be on that direction.