Secrets

Four close friends break into their high school one night, you know "living in the moment" and whatnot. While exploring the school... they stumble across the basement. They put a doorstop in it just to make sure they don't get locked in, they fool around for a little bit down there not finding anything to do so they decide to leave. But on their way out... they noticed the door was shut. And now they are locked in the basement with no wifi or phone signal... they are screwed. Accepting that they will be stuck in there all night they decide to explore a little bit. one of them finds an old chalkboard, and they summon the others. They stared in disbelief, on the top of the chalkboard all of their names were written. Underneath their names, it said, "EACH OF YOU IS HIDING SOMETHING FROM EACH OTHER." They all start freaking out, but written at the bottom it said, "IF ANY OF YOU FAIL TO TELL YOUR TRUTH BY MORNING... YOUR SECRET WILL BE UPLOADED TO YOUR SOCIAL MEDIA ACCOUNT." Who knows their secrets?? Who locked them in the basement??? Will they make it out as friends???