The Return of Zaalim is a canceled Zoo Tycoon 2 machinima made by ZoTicc. It has been very popular around YouTube, and is becoming more popular overtime as more people are viewing it.
The story takes place during the mid - 21st century, when humans have been learning to be more civilized then before. Victor Cone, the head of a secret organization, has been told that an immortal being is threatening to perish all life on the planet Earth, and shall be returning to Earth in two weeks time. Victor decides to name the being Zaalim. The reason why Zaalim shall return to Earth, is that it was Zaalim that caused the dinosaurs to extinction. The next day, Victor announces the news, while he is being aware that this event shall change the history of Earth for all eternity.
The Return of Zaalim is not based off of a book or movie, although there is an Idian movie called "Zaalim".
The Return of Zaalim: Trailer 
The Return of Zaalim: Episode 1 
The Return of Zaalim: Episode 2