Walt Disney's Comics and Stories #8 (176)

Huey innocently asks Donald what day it is, and the duck, deep in a newspaper, declares it’s Friday—payday. But when he checks his meager twenty-one cents, the realization dawns: it’s actually Thursday.

Mickey and Goofy take a scenic flight in their air taxi to deliver a professor to a remote Mexican expedition, where they soon meet the contrasting twin brothers Panchito Luis and Alvaro Xavier Miguel Sanches Potosi—only one of whom has a shady past. When the criminal twin, Pepito, suddenly abducts the professor, Mickey and Goofy must use their wits and teamwork to track him down before the lost city remains buried forever.