"I will," he promises, low and flat.

He will not. Mako will retreat into himself again, try to keep himself from falling apart with the memory of Wu's wrist snapping and the gaping space next door from which his friends disappear.

But here, in the quiet kitchen with Evelyn's voice on the other end of the line, he makes a promise that he can't keep. "I'll let you know, Evelyn. Stay safe."