Late summer off some cold-water coast brings the plankton bloom to its peak, and the food chain above it responds in sequence. Herring gather in vast shoals to feed on the plankton, and the film follows the chain reaction that follows: diving seabirds drive the fish into a tight, swirling bait ball near the surface, working as a coordinated pressure system rather than a scattered attack. Then a humpback whale surges up from below and takes the entire ball of herring in a single mouthful, a moment the cameras catch at close range as the water erupts. The sequence is a compact case study in ocean predation, showing how a bloom invisible to the naked eye cascades upward through fish, birds, and finally one of the largest predators in the sea. It is a brief, single-scene account rather than a full survey of the events referenced in the series title, built around this one hunt from start to finish.