Illegal aliens are being flown in from Mexico by small plane. When a Secret Service agent finds out, he is killed and the smuggling is shut down for awhile. Brass, an ex-Navy flyer who is now flying the Pacific Clipper route, is chosen by the Service to find out who is behind this smuggling ring. Since they know that an ex-smuggler named Ace was part of the gang, Brass is put into the general prison population to try to get information from him. It is from Ace that he learns where the smugglers are located, but it is up to Brass to infiltrate the ring and bring the head man across the border to be arrested. Written by Tony Fontana

In the first in a series of four films featuring the character: Transport pilot, "Brass" Bancroft, former U.S.Navy pilot, is hired by the U. S. Government to get needed evidence against an alien-smuggling gang operating along the Mexican border. In order to get him inside the gang, he is jailed, where he gains the confidence of one of the gang members and, after they make a set-up escape, 'Brass" is accepted into the gang as a pilot. Working from inside the gang, led by Jim Cameron, "Brass", with the aid of his pal, "Gabby" Watters and secret-service agent Saxby, is instrumental into bringing the gang to justice. Written by Les Adams