Begel, the leech, is not an ordinary bloodsucker. On the contrary, he diligently goes about his work in the veterinary practice. In the morning, he does his gymnastics, then he treats the patients, and in the evening, he tends to the river sand at the bottom of his glass. Begel knows that a lot depends on him. That's why he doesn't understand why he suddenly has to share his cozy glass with the scrawny Ögül. At this point, the leech is unaware of the giant dog patient and how uncomfortable it can be outside his little home. As a therapy animal of a different kind, Nele Brönner has her leech undergo an aggregative metamorphosis: sometimes heavy like a thick drop of tar hanging from the glass wall, sometimes fully engorged and bouncy like a rubber ball, and then again brittle, rough, and battered. Nele Brönner demonstrates that leeches can do more than one might think.