US Navy laser gun in action!
You normally only see laser guns in sci-fi flicks on the big screen, but they're real - and they're being used at sea off the American coast.
The US Navy has kitted out one of its ships with a laser gun for the first time.
They hope that the high tech gear will be able to stop enemy boats by using the laser beam to damage their engines.
Lasers have been used on land for years but they haven't used at sea because the damp air reduces their power.
In tests researchers have used the high-energy laser (HEL) to disable a boat by shooting the beam and setting fire to its engine.
The US Navy hope that the technology could soon be used to protect ships from attacks by smaller boats.
Experts have been working on the technology since the 1970s, but have had trouble designing a beam that isn't harmful to the people using it.
The lasers are still in the test stages so it could be a few years before they are rolled out across the seas!