This is a giant asteroid hitting the earth every million-years kind of trouble. Ergo, we have divine intervention by way on one Granny Smith. She is an angel in The Big Being's secret service. Of course, we kids did not know that when we first met her. Now angels can not meddle directly in human affairs, so Granny needs the help of human beings to get her mission accomplished.
Kids are much better at believing in angels, and other so called imaginary creatures, than grownups.
S.M.O.G.I.I., or Scientific Mobilization of Global Industries International, is trying to recruit the trillionaire Johnathan Longfellow into their ranks. If they do it the tide of battle will shift even more in their favor. Agent Omega, S.M.O.G.I.I.'s top corporate spook, is in charge of turning Johnathan rotten. If they can gain control of Johnathan's vast ocean fisheries, they can cause a ocean-wide plankton die off. Granny Smith had a minor brush with the fellow ages before, and he somehow swiped her anti-aging formula.