When two scientists notice a huge section of coral reef bleaching from acidic waters, Gordon launches in Thunderbird 4 to discover the cause. Under the water, he finds a sunken cargo ship containing dangerous acidic materials.
Casts:
Rasmus Hardiker, Chris Jarman, David Menkin, David Graham, Sandra Dickinson, Jenna Coleman, Adjoa Andoh, Thomas Brodie-Sangster, Angel Coulby, Kayvan Novak, Rosamund Pike, Teresa Gallagher