With Walt Disney Studios' announcement that a fifth Indiana Jones movie is in the works, it's time to celebrate the 40th anniversary of George Lucas and Steven Spielberg's blockbuster film franchise about the adventures of a swashbuckling archaeologist. Indelibly embodied by Harrison Ford, the man in the fedora is dashing and irresistibly human, braving all manner of heart-stopping danger while battling Nazis, Stalinists and other foes in his quest for priceless artifacts—always with humor and panache. LIFE traces the evolution of the film series, from its roots in 1940s serials and action flicks through the creation and production of Raiders of the Lost Ark and three rollicking sequels. With a lively, incisive narrative and a rich trove of photos, this special edition features plot summaries, actor profiles, and a wealth of behind-the-scenes anecdotes—a fitting tribute to one of cinema's most beloved and enduring heroes.