The Secret Engine: Part 1.The elderly son of a deceased gangster drives a Model T that contains a code for a missing haul of stolen money, a haul that Tongue Blaggard, a brutal gang leader, is determined to find. During this episode, Speed attends a road racing school where Racer X suddenly appears, wheels the Mach 5 through a tricky slalom course, and thus intimidates the other drivers and the school instructor, but not Speed; Racer X also chances upon Pops, Mom and Speed, all remembering Rex and saddened in wishing he would return - a wish Rex quietly vows to someday keep...