Threatening note

"Another note? It says, 'Brew it quickly or find yourself fast-tracked to retirement!', and it's signed with the initials 'A.B.'! It sounds like Bilius was being blackmailed!… But who's this A.B.?"

- Mathilda Grimblehawk, upon discovering the threatening note in St. David's Hospital

This threatening note was sent by Astor Bellchant to Bilius Finbok, threatening to expose his illegal potion-making business if he did not hurry in brewing a mental acuity potion for Bellchant's son Albert, who was failing Transfiguration, Charms and Herbology at Hogwarts School of Witchcraft and Wizardry.

Finbok had, at the time, been injured by a Runespoor, and had been taken to St. David's Hospital by his Muggle neighbour Sara Farnham, who had found him unconscious. As noted by Nurse Babatola, Finbok ran away shortly after being hospitalised, though he did note that there was an owl sitting outside the window there around the time he vanished. Ministry of Magic investigators Mathilda Grimblehawk and her partner later found this note in the ward, and used it as evidence during the course of their investigation of Finbok's whereabouts and illicit activities.