In the Potions classroom, Alistair spread his potions textbook open, letting a corner of that letter poke out, then got up to go to the front desk to collect the potions they had started brewing last time.
The potion they needed to brew this time was extremely complex, requiring a full month to complete, and they had already been working on it for two solid weeks.
As he brewed the potion, he kept an eye on the state of the people around him. Everyone was diligently working on their potions, and he couldn't tell which student might be the one who had sent him the letter.
Chapter 423