Scoob!

The action of the film begins in the 90s of the last century, when a Great Dane puppy steals a rack with a gyros from a store. He is chased by a policeman and eventually comes across a lonely boy, Norville "Shaggy" Rogers. Shaggy shares her sandwich with the puppy, who adds some giro meat to it. The officer finds the dog and asks Shaggy if it's his dog and what her name is. He calls the dog Scooby Dooby Doo, and the officer leaves. Shaggy brings Scooby home and gives him his trademark collar. From that moment on, they become best friends. On Halloween night, Shaggy and Scooby dress up in costumes of their heroes - the Blue Falcon and Dinomut. They pass by a creepy house and encounter hooligans who throw candy into the house. A moment later they meet a trio of friends - Fred Jones, Daphne Blake and Velma Dinkley. They decide to go into the house together, where they stumble upon what seems to be a ghost. The children are trapped in the house until Fred and Velma notice the rope holding the ghost and untie it. They expose him as a local resident, Mr. Rigby, who also hides stolen groceries from the store. He is arrested, and he blames these wayward children for his misfortunes. After that, the four friends and Scooby take an oath to continue to uncover secrets together under the name "Mystery Inc"...