Presents the story of whale sharks-- the largest fish on the planet. Facing threats from commercial fishing as well as climate change, they were categorized as endangered in 2016. Despite the marine sanctuaries set aside to protect whale sharks, their population is still decreasing. These gentle giants may be accidentally caught in fishing nets, fished by poachers, or hit by a ship's propeller. But new conservation methods, which include enlisting volunteers to spot them as well as tagging and remotely following them--are giving experts hope. Can volunteers and scientists help save the world's biggest fish before it's too late?

Trapped! -- Whale sharks in trouble -- A mysterious life -- Oceans of problems -- Safe havens -- Ocean detective tools -- Rescued! -- Great whites need help too -- Author's note -- You know? -- Timeline.