The Marauders are ready to start their last year. But before it even starts, they find themselves in trouble. On the Hogwarts Express, they have an unfortunate encounter with a girl who appears to be a Slytherin. After she slaps James, things get even worse. She befriends James’ love interest, Lily Evans. There is a lot more behind this soft-spoken, pretty, polite but strong girl that they don’t know, and Sirius is determined to find out.

 First class of the year, and McGonagall gives them detention. Typical start. The next day, in Potions, they brew Amormentia. And what else should Sirius smell in his potion but roses?

 The Marauders are rewarded for their excellent start to the year with a weekend in Hogsmeade, although they’re technically banned. Further excitement is added by the first official Quidditch practice and the first Full Moon. But as the full moon comes and goes, Sirius still does not understand why Rose is the target of the Slytherins.

 After witnessing soft-spoken, sweet Rose hex a group of Slytherins into oblivion, James and Sirius don’t know what to think. It’s obvious that Rose is hiding something from them. Something important. Something about her family. But she is so distraught after it happens that McGonagall doesn’t even give her detention, and Sirius isn’t about to ask her about it. Later, after the boys’ own detentions, they eavesdrop on Lily and Rose talking – is there a chance that Lily might finally agree to go out with James?