Sam Witwicky is the main human protagonist in the Transformers live-action film series. He is an ordinary teenager who becomes unexpectedly involved in the war between the Autobots and Decepticons after discovering the AllSpark and meeting Bumblebee. Across the films, Sam grows from a confused high school student into a brave ally who helps the Autobots protect Earth. His role is central as a human bridge between the Transformers and humanity, often driving the story forward through his discoveries and actions.