They make their way around the headland just in time to avoid being washed out to sea by the implacable tide. In front of them is a muddy tidal flat, forming the floor of a box-shaped cove. The walls of the box are formed by the headland they’ve just gone round, another, depressingly similar headland a few hundred yards along the shore, and a cliff rising straight up out of the mudflats. Even if it were not covered with relentlessly hostile tropical jungle, this cliff would seal off access to the interior of Guadalcanal just because of its steepness. The Marines are trapped in this little cove until the tide goes back out.