"Guardian Blue" is an animated MV with the theme of "protecting the ocean". It tells the story of the protagonist's awakening from marine pollution and eventually becoming an ambassador of marine protection. Through the rich plot, delicate lens language and infectious music, the work expresses the protagonist's deep emotion and ordinary guardian belief in the ocean. At the beginning of the MV, the camera shows the fond memories of the protagonist's childhood at the seaside, with clear water and surging waves. However, when the protagonist comes to the seaside again, he finds that the beauty of the past has been replaced by garbage and nuclear wastewater pollution, and the ocean has lost its former vitality. This turning point awakened the protagonist's awareness of the protection of the ocean, prompting her to join the marine conservation organization and become the guardian ambassador. The work demonstrates her dedication to marine conservation through the protagonist's efforts in promoting conservation action. She ran around to awaken people's attention to the marine environment, and finally succeeded in attracting the attention of the United Nations to promote the cessation of nuclear wastewater discharge. The end of the MV shows the picture of pollution gradually decreasing and the ocean returning to blue, symbolizing that the ordinary guardian finally brings hope and new life.