In this family comedy, we follow the antics of a gigantic and mischievous Great Dane named Marmaduke, who lives with his family, the Winslows. When his owner, Phil, decides to move with his wife and three children to a new city, Marmaduke feels out of place in his new home and new life. With a house full of new smells and the challenge of making friends, the enormous dog quickly realizes that fitting in won't be so easy.
Determined to conquer his new neighborhood, Marmaduke embarks on a series of disastrous adventures, including a fight with a very aggressive cat and the inevitable rivalry with other dogs. Among new canine friends and adversities, Marmaduke's heart fills with love for a beautiful dog named Jezebel, but he is also dealing with the pressure of being a popular dog in the neighborhood.
As he navigates his social life and faces the possibility of losing his family's attention, Marmaduke quickly learns lessons about loyalty, friendship, and the importance of being himself. With a light-hearted tone and sweet humor, the movie addresses the experiences of growing up and finding your place in the world, all from the perspective of this charming yet often clumsy dog. In the end, Marmaduke shows us that no matter how big or small you are, you can always find your place in life.