kim is 11 and jim is 7, they are two ordinary primary school students living in beicheng, china. during a thunderstorm, they accidentally create a wormhole that connects a time tunnel. different ancient animals travel through the wormhole and become their best friend and a big secret. wormholes open at irregular times, often giving them trouble or different choices, sometimes in the middle of summer to send a hot mammoth, resulting in summer make-up lessons into a canteen ice carnival、sometimes tyrannosaurus rex, who liked to dance to music, would break into the school to report on the show. sometimes the mischievous twin velociraptor makes a mess in the bedroom before their mother gets home... in each episode, the oddest siblings face the challenges of a wormhole, hiding in front of their parents, teachers,and classmates... however, as the wormhole opened and closed more and more erratically, a five-stories high mamensheosaur brought its secrets to light. kim and jim finally confessed to mom and dad, love and tolerance let them together in a critical moment, teachers and students are also to help, to deal with the attempt to use the wormhole to save their bankrupt company of technology tycoon melonma. in the moment of crisis, kim and jim also realize that they are necessary for the wormhole to open. in order to protect the animal friends in the wormhole, kim bravely chose to enter the wormhole. crisis lifted, kim alone trapped in the ancient times, everyone is looking forward to the wormhole once again open ……