Grunther is a henchman of Ernst Stavro Blofeld and head of Piz Gloria's security. He along with Irma Bunt, Blofeld's righthand woman and henchman, wait for Sir Hilary Bray, who is actually James Bond in disguise, and denys Bond's ally, Shaun Campbell, access into the allergy clinic and then kills Campbell after Campbell tries to scale the mountain face of Piz Gloria. When James Bond is discovered by Blofeld, Grunther knocks out Bond and restrains and escorts Bond to his new room. When James Bond escapes, Grunther alerts Blofeld of his escape.
He is killed by Tracy, Bond's love interest and wife, when she impales him on a set of ornamental wall spikes hung on the wall at Piz Gloria.