Wilhelmina Grubbly-Plank

Professor Wilhelmina Grubbly-Plank is a Witch and a substitute Care of Magical Creatures professor at Hogwarts School of Witchcraft and Wizardry. She is a competent and knowledgeable magizoologist who temporarily replaces Rubeus Hagrid on two separate occasions. While her presence often indicates trouble for Hagrid, she serves as a reliable and professional educator, offering a more conventional and safer teaching style that provides a stark contrast to Hagrid's own methods.

Professor Grubbly-Plank first appears during the 1994-1995 school year to teach Care of Magical Creatures after Rubeus Hagrid goes into hiding. His absence is a result of a slanderous Daily Prophet article by Rita Skeeter which exposed his half-Giant heritage. Her lessons are considered informative and much less dangerous than Hagrid's; she brings a Unicorn to one of her first classes, much to the delight of many students. While Harry Potter, Ron Weasley, and Hermione Granger are initially worried about her replacing their friend, they acknowledge her competence. She returns to Hogwarts at the start of the 1995-1996 school year, once again substituting for Hagrid, who is away on a secret mission for the Order of the Phoenix to recruit the Giants. During this time, she endures the scrutiny of High Inquisitor Dolores Umbridge. Grubbly-Plank handles Umbridge's classroom inspections with professionalism, asserting that Headmaster Albus Dumbledore has approved her lesson plans. She also staunchly defends Hagrid's expertise when questioned by Umbridge. During this period, she skillfully tends to Hedwig's injuries after the owl was attacked. She departs her post upon Hagrid's return to the castle. Her activities following her second tenure as a substitute professor are unknown.

Professor Grubbly-Plank is described as a Witch with grizzled grey hair cut very short and a prominent, jutting chin. She is also known to smoke a pipe. She has a gruff, no-nonsense demeanor but is fundamentally a kind and capable individual. Her professionalism is evident in her organized lessons and her calm handling of Dolores Umbridge's interrogations. She is loyal to both Dumbledore and Hagrid, speaking highly of the latter's skills. Her kindness is most apparent when she gently and effectively treats Hedwig's injuries.

• Magizoology: Grubbly-Plank is a highly proficient magizoologist with extensive knowledge of a wide variety of magical beasts. Her lessons cover creatures such as Unicorns, Bowtruckles, and the proper handling of Flobberworms, demonstrating a firm grasp of the standard Ministry of Magic curriculum.
• Healing Magic: She displays considerable skill in healing animals, as shown when she successfully mends Hedwig's wing and other injuries, a task that proved difficult for others.

• Pipe: She is often seen smoking a pipe.

Professor Grubbly-Plank holds Rubeus Hagrid in high regard, respecting his profound connection to and knowledge of magical creatures. She defends his abilities to Dolores Umbridge and serves as his trusted replacement. She is loyal to Albus Dumbledore, who twice entrusts her with the Care of Magical Creatures post. Her relationship with students is professional. While the Gryffindor trio worries about her as a symbol of Hagrid's absence, other students, including those in Slytherin house like Draco Malfoy, treat her with a level of respect they never afford to Hagrid.

• Wilhelmina: This is a German name meaning “will-helmet” or “desiring protection.” This could allude to her role as a stable, protective teacher who ensures student safety in her classes.
• Grubbly: This name suggests an earthy, “grubby” quality, fitting for someone who works closely with creatures and the outdoors. It also contributes to her gruff first impression.
• Plank: A plank is a flat, sturdy piece of wood, which may reflect her straightforward, solid, and reliable personality and teaching methods.

In the film adaptation of Harry Potter and the Order of the Phoenix, Professor Grubbly-Plank is portrayed by actress Apple Brook. A notable change in the film is that Grubbly-Plank, not Hagrid, is shown introducing the fifth-year students to Thestrals. In the novel, this memorable lesson is taught by Hagrid upon his return to Hogwarts. (film)