I wouldn't ruin the plot (unless asked), but I would make it clear that the commercials are being dishonest about the implied plot.
The movie is a scam, in that its selling tickets by pretending its a girl version of Rocky, with the whole underdog, and mentor thing, when its really selling something that is totally different and in no way related to any type of sports movie.
Please do tell the plot, although I am beginning to get a piciture of it from this thread.
Popular culture sure is creating euthanisms for a lot of bad stuff.