So far, the guerillas under General Chiu, and the secret squadron agents under Captain Midnight, have prevented the huge Jap army from pouring across the pass, which is the last barrier protecting the hidden runway. As a last desperate measure, five steel drums, filled with fragmentation bombs, were rolled down the mountainside, exploding with terrific force as they reached the bottom. In addition, Captain Midnight has sent word to Chuck to take off in his Jap fighter on a mission too. While all this is taking place, Ichabod Mudd, helped by Joyce, is working desperately to install the release mechanism for his secret weapon in the Jap bomber flown by Spike Randall.