Goodbye, Mount Emily: Book 4 - Mount Emily, #4

In the concluding book of the Mount Emily series, Patsy and Elena are now in Secondary Four and face having to leave Mount Emily Girls' School by the end of the year. However, they soon find that graduating from their beloved school is the least of their concerns, as unexpected circumstances lead them to have a final showdown with the Midnight Warriors, and in so doing, change the course of time travel forever.