Mark is an ordinary truck driver living a poor life, especially since his daughter and her husband died in a car accident, leaving him to take care of his two grandchildren. In his need of money, he accepted an extra job recommended by a friend but has an accident on the road. Instead of going to jail, however, he finds himself in a strange situation for his truck talked in his mind. Every now and then, he is given a task to complete in order to receive rewards.  Soon Mark discovers that, despite his good-willed nature, he has no choice but to accomplish those tasks in order to not be sanctioned by the system, making his granddaughters orphans. To not let his granddaughters down, he has to become the Truck-kun driver.