A stocky and imposing character, Grunther is Blofeld's head of security at the Piz Gloria allergy clinic; the SPECTRE chief's Alpine hideout. Along with Blofeld's closest aide Irma Bunt, he is first seen waiting for genealogist Sir Hilary Bray at a Swiss train station, unaware that Bray is actually James Bond. After welcoming Bond to Switzerland, Bunt instructs Grunther to take his luggage and they leave for the clinic.
After arriving at Piz Gloria, Grunther covertly examines Bond's luggage before taking him to his room. Bunt explains that Grunther will open his externally locked door and escort him if he needs to leave his suite. This 'complicated arrangement' is in place for all Blofeld's guests; supposedly to prevent them from disturbing one another. Consequently, Bond is under his constant supervision during his stay at the clinic.