In March 1945, he and his son, Seigfried, and several colleagues went to Glastonbury in the United Kingdom to attend the annual conference on Holy Grail lore. He consulted Professor Henry Jones about what he knew about the Spear of Longinus. Realizing that these men were probably Nazis, Jones contacted his son, Indiana Jones, working on a dig in Ireland, about the potential threat. Dieterhoffmann was already having the young Jones monitored by his contacts among the Blueshirts, and ordered that the younger Jones be killed.