All their problems had started two hours ago, during double Herbology class, in the second hour of the morning. That day they were facing the Venomous Tentacula, a horrible and dangerous plant that had the ability to catch prey alive. And it was an ability they had seen firsthand. While Ron was trying to collect the poison coming out of its buds with a pot, and Hermione was trying to prune its sharp defensive spikes with magically reinforced scissors, Harry had been caught by one of its tentacles. The sturdy plant had wrapped around his left ankle, discreetly, unnoticed, and then unexpectedly waved him through the air like a doll. After his friends tried several desperate spells, and thanks to the quick intervention of Professor Sprout, who was saving Neville from being strangled by another Venomous Tentacula at the next table, they managed to rescue the boy. However, his left leg had not fared too well. He had dislocated his ankle where the plant had grabbed him with its tentacles, and he had hit his knee, fracturing the lower part of his femur.