Stargate Atlantis (2004)

S3E12 Echoes

The residents of Atlantis face dire consequences as the planet's whale population starts to migrate to their island city. This unusual influx signals a looming disaster, causing distress among the inhabitants. As the whales arrive, the once-peaceful environment shifts, leading to a series of unsettling events that threaten the very foundation of their society. The Atlanteans must confront the mystery behind this phenomenon and its ominous implications for their future.