Supernatural (2005)

S9E5 Dog Dean Afternoon

In a bid to find a murderer, Dean utilizes a spell that enables him to communicate with the sole witness—a German Shepherd. However, things take a bizarre turn when the enchantment begins to influence Dean's behavior, causing him to adopt canine traits. As he navigates this new reality, he must balance his quest for justice with his unexpected transformation into a dog-like state.