It's been five years since the last shark-Armageddon that devastated Washington, D.C. in Sharknado 3: Oh Hell No! (2015), and the world can now benefit from this hard-earned peace, thanks to Aston Reynolds' revolutionary atmosphere stabilisers. However, as Fin is heading to Vegas for a family reunion, in the meantime, menacing clouds are beginning to form, and a brand-new Sharknado formation is at hand. Under those circumstances, once again, Fin, his old friends, and some new ones will have to battle against massive shark-infested cyclones, in a colossal Sharknado extravaganza with thousands of razor-sharp teeth. More and more, mutated types of evolved cyclones destroy everything in their path, as the mother of all Sharknadoes awakens. Can Fin dodge a bullet for the fourth time?