Captain Holt: Now, what do we do about the rats?
Charles: Well, lucky for us, I have recently come into a lot of wolf urine.
Rosa: That's lucky for us how?
Charles: It creates a scent impression that there are predators nearby. I've been dousing Nikolaj's shoes with it to scare off bullies at his preschool.
Rosa: Did it work?
Charles: No, now they call him pee boy. He's much worse off. But wolf urine definitely scares off rats. We can use it to herd them toward the traps.