From their website:
Players in Elder Sign assume the roles of investigators racing to prevent the Ancient One from entering the world through gates from other dimensions. As the time to doomsday dwindles, investigators desperately hunt for Elder Signs, the potent eldritch symbols needed to close the gates and seal the Ancient One away forever.
Should they fail, the Ancient One’s elder might threatens to reduce all humanity to cinders.
Witness the beginning of the end times investigators must prevent in our Elder Sign video