It's late in the morning of August 8, 1942, on the island of Guadacanau in the South Western Pacific.

27-year-old Marine Captain Bill Ringer hacks through the thick vegetation with his machete.

Guadacanal is a 2,000-square-mile island of mountains and dense jungle.

The heat is unbearable, the ground is like a swamp,

and insects have already bitten every exposed patch of Ringer's skin.

But he can't stop or turn back.

He's part of Operation Watchtower, the first major

U.S. offensive in the Pacific War. Alongside the rest of the 5th Marines Division, Ringer's

mission is to try and take a half-built airfield from the Japanese. But Ringer has to make it

through the undergrowth first. Suddenly, Japanese planes roar overhead.

Ringer and the other Marines drop to the ground and flatten themselves into the mud.

But the Japanese don't seem to spot them.

Instead, the planes keep flying directly out to sea.

Ringer waits until he's sure they've gone, then signals for his men to continue.

It's not far to the edge of the jungle.

In pushing aside the last of the leaves and vegetation, Ringer gets his first look at their target.

The airfield is just a muddy runway with some ramshackle huts alongside it.

But Ringer knows he could help decide the war in the Pacific.

Whoever holds it will have air superiority over the crucial supply line between Australia and the United States.

So if the Allies are to triumph, they have to take this airfield.

Ringer checks his weapon and then moves forward quickly, expecting gunfire at any moment.

But as he advances, there's only

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