The China Syndrome

Jack Godell (Jack Lemmon) notices an unusual vibration while grabbing his cup of coffee which he had set down. He then finds that a gauge is misreading and that the coolant is dangerously low (he thought it was overflowing) The crew manages to bring the reactor under control and can be seen celebrating and expressing relief. Experts conclude that the plant came perilously close to the China syndrome in which the core would have melted down.