*CAUTION: POST CONTAINS SPOILERS*
The code for the keypad in the bathroom of the diner is 0311.
There are many codes written all over the wall but this one is not easily noticed. The one hint you get is that the mirrors aren't reflecting anything.

Embark on an inspiring mission of human connection beyond the UCA. Sam — with companions by his side — sets out on a new journey to save humanity from extinction. Join them as they traverse a world beset by otherworldly enemies, obstacles and a haunting question: should we have connected?