The Proof Is Out There — Episode 24: UFO Window Seat and Lost Underwater City

You are watching the episode UFO Window Seat and Lost Underwater City Shocking sighting of a UFO outside from the window seat of a passenger jet. A strange underwater discovery is said to be a lost Japanese city. And are giant sloths responsible for a series of tunnels in Brazil? Tony and team investigate some of the world's strangest photos and videos.