多年前，女孩无意间邂逅了一条白色的北京犬——雪球，这条可爱的狗狗陪她度过了美好的童年。当女孩逐渐长大，雪球却意外地去了另外一个世界。在极度的内疚和悲伤中，女孩不再养狗。多年后，不知内情的男友却再次送来一条黑色贵宾犬。它显然不同于雪球，调皮捣蛋，恶作剧不断，甚至分辨不清谁是主人......但就是这样一条劣迹斑斑的小狗，给寂寞的女孩带来了快乐，解开了她的心结。然而当女孩的爱情遭遇危机，以往顽皮的狗狗也重病不起，生命垂危......宿命，还是轮回？谁，来拯救一段濒危的爱情，和一个忠诚的朋友？（Years ago, the girl encountered a white Pekingese and named it Snowball. With the dog, she experienced a happy girlhood, but when she grew up, Snowball was accidentally killed. Depressed in guilty and grief, she decided not to keep any dog again. Years later, her boyfriend, without knowing the story of Snowball, gave her a black Poodle. It was obviously not as naughty and mischievous as Snowball, but even cannot identify its owner...Nevertheless, this troublesome dog brought much happiness to the lonely girl and healed her scar in heart. Unexpected crisis occurred in her relationship with the boy, while the dog got seriously ill... Is this destiny or reincarnation? Who can save them from the love crisis as well as the life of a loyal friend?）