Super-villains HEATWAVE and CAPTAIN COLD don't like the FLASH, but they don't like each other either! They face off in a climate-changing smackdown that could spell disaster for Earth's ecosystems. The FLASH tries to take the foes one-on one, but ends up encased in arctic ice. Unable to move, FLASH watches as HEATWAVE turns up the threat level by melting the frozen seabed ...a sea full of explosive methane gas!