He stumbled into the fluorescent sanctuary of a corner bodega, the bell above the door chiming like a victory trumpet. The air conditioning hit him in a frigid wave, pulling the salt from his skin.

Leo stepped back out into the heat, the bottle sweating in his hand, feeling like he could run another ten miles—or at least walk the rest of the way home.

He headed straight for the back, where the glass-fronted coolers hummed. Behind the condensation-beaded doors sat the rows of liquid neon. He didn’t want water; he wanted science. He wanted electrolytes.