The junior Mueller was a Boy Scout and in 1912, Herman and his friend Indiana Jones went on a Boy Scout equestrian camping trip together in Utah. After separating from the rest of the troop, Herman and Indy explored a cave in a canyon, where they discovered Fedora and his crew digging up the Cross of Coronado. Indy sent Herman back to find Mr. Havelock and inform the Sheriff that there were looters in the caves. After being scared by a snake, Herman took off on his mission.
Shortly after Indy returned to his house, Herman showed up, announcing his arrival with his bugle. He had succeeded in bringing the sheriff, but the lawman took Fedora's word for it that the relic was stolen from him and his gang. The Cross was returned to them and presented to Panama Hat, who was seen as the rightful owner.
Behind the scenes
In the earliest scenes of the film, J. J. Hardy accidentally fell of his horse. Such scene wasn't scripted after all, according to Hardy, who says that his leg hit the backpack as he was trying to get off and he ultimately lost his balance.
In the caves scene where they are separated, Indy didn't tell Herman he would return home or any other appointment after retrieving the Cross of Coronado, saying only 'I don't know... I'll think of something' instead. It is not therefore explained how Herman knew that Indy would be home, and why he decided to take the Sheriff there.
Several other characters are near carbon copies of Herman; among them are Herbert Wozcinsky from Indiana Jones und das Verschwundene Volk and Ketts from Young Indiana Jones and the Mountains of Superstition. It has been speculated that the authors of these stories intended for these characters to be Herman, and that the actions (or inaction) of Lucasfilm Ltd.'s continuity department resulted in the discrepencies.
In LEGO Indiana Jones: The Original Adventures, filling the second player character slot, Herman joins Indy in his escape from the caves and during the chase on board the Dunn & Duffy Combined Circus train. As such, he also escapes from Fedora's clutches by performing the magic trick along with Indy in Doctor Fantasy's Magic Caboose. In the sequel, the whole Young Indy sequence is left out, but Herman still depicted in a photograph when Marcus Brody instructs Indy and, in this version, Sallah about their mission to retrieve the Cross.
- Indiana Jones Jr et le Fantôme du Klondike
- Young Indiana Jones and the Princess of Peril (Mentioned only)
- Indiana Jones Jr et le Violon du Metropolitan
- Indiana Jones Jr et le Triangle des Bermudes
- Young Indiana Jones and the Ghostly Riders (Mentioned only)
- Young Indiana Jones and the Circle of Death
- Young Indiana Jones and the Secret City
- Indiana Jones and the Last Crusade (First appearance)
- Indiana Jones and the Last Crusade novel
- Indiana Jones and the Last Crusade comic
- Indiana Jones and the Last Crusade junior novel (1989)
- Indiana Jones and the Last Crusade junior novel (2008)
- LEGO Indiana Jones: The Original Adventures (Non-canonical appearance) (As "Boy Scout")
- LEGO Indiana Jones 2: The Adventure Continues (Non-canonical appearance) (Pictured only)
- Indiana Jones: The Ultimate Guide
- The Greatest Adventures of Indiana Jones
- Top Trumps: Indiana Jones