RIMPAC is the biggest naval operation in the world involving 28 countries around the Pacific. There are explosions, exercises and loads of ships.
In the centre of this all is Kiwi Hayden Smith. But rather than storming the beaches, he's cleaning up.
For the past 14 years, Mr Smith has been helping clean up New Zealand's coastlines and his organisation, Sea Cleaners has picked up plenty of plaudits and admirers.
His talent for improving our beaches and waterways caught the eye of one of the most powerful military forces in the world.
His experience impressed the Americans who invited him to help clean up Hawaii's stunning coastline.
Mr Smith took along some high-powered friends for the ride including Captain Andrew Watts of the Royal New Zealand Navy.
So why Hawaii specifically and what did the Kiwis think of the experience?
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