It's her eighteenth birthday and her "ET" loving parents are waiting with their cake for daughter "Elliott" (Maisy Stella). She's off with her pals though, camping out and drinking a particularly potent mushroom tea. Next thing, she finds herself sitting on a fireside log chatting to a thirty-nine year old version of herself (Aubrey Plaza). Hallucinating? Well yes, but somehow her older self manages to leave her a phone number and give her a little advice about her future with the as yet unknown "Chad". Next day she's doing a bit of skinny dipping and guess who she meets? There's the semblance...