Dramatic cell phone video captures the brain’s threat detection and response in action when a young girl sitting on the edge of a wharf is suddenly dragged into the water by a sea lion. Like a bolt of lightning a bystander instantly leaps into the murky water to rescue the child from the jaws of the agile marine mammal attacking the helpless girl. This incident is a dramatic example of how our brain is wired to react instantly and aggressively in response to certain specific triggers, which activate distinct neural circuits in the brain’s threat detection mechanism, and to do it without any conscious deliberation. Whether this selfless aggressive response was launched by the F or the T trigger in the LIFEMORTS mnemonic depends on whether the hero in this case was a family member or a stranger, but this information is not yet known.