A wealthy student with too much fashion sense, her equally rich friends, and her rival/superior from the school paper work together to solve the case when their teacher goes missing.
Decent watch, probably won't watch again, but can recommend, particularly for younger audiences.
It's definitely inspired by Nancy Drew (they drop the name somewhere as a joke), but isn't one itself.
It's a good coming of age / identity story about investigating a mystery: it's somewhat funny, but the premise is that it's stuck up little rich kids (mostly) that have to get a taste of the real world.
Sadly, kids and adults, Lindsey Lohan pretty much carries the movie. She does a good job but other actors really had a chance to stand out in this and just didn't.
It's not a bad movie, but really, there are other mystery movies, and I'd recommend "Nancy Drew" (Emma Roberts) or "Nancy Drew and the Hidden Staircase" (Sophia Lillis) over this.