Animals across this series turn out to sense and do things far outside human range: sharks that detect the faint electric field around a human body, dolphins that use ultrasound to watch a human fetus develop in the womb, and pet dogs and cats that seem to react before earthquakes strike. The film moves from species to species collecting cases that sound like folklore until researchers explain the biology behind them, including wood frogs that freeze solid for roughly six months and thaw out alive, horned lizards that squirt blood from their eyes as a defense, and basilisk lizards that run across open water on specially adapted feet. It also takes on stranger reported phenomena, fish falling from the sky in isolated rainstorms and bacteria that appear to concentrate gold from their environment, treating each as a real observation with a scientific explanation rather than a mystery left unsolved. The throughline is sensory: these are abilities built into ordinary biology, just tuned to frequencies and signals humans cannot perceive on our own.