Einstein (portrayed by Tiger and stuntman Dick Butler in the first film and Freddie in the other two, voiced by Danny Mann in the animated series) is Doc Brown's pet Catalan sheepdog. He later becomes one of the main characters in the animated series as the Brown family's dog.
In the first film, Doc successfully tests his time machine by placing Einstein in it and sending him one minute into the future. In the animated series, Einstein becomes anthropomorphic and smarter, helping Doc with his inventions for traveling to the past and the future.
