The initials OHMSS stand for "On Her Majesty's Secret Service." It's the title of a James Bond book by author Ian Fleming.
And it is also the name of the very best 007 film made so far in the 24 Bond movies. Including the excellent Casino Royale and Skyfall.
OHMSS features the best Bond Girl (Diana Rigg), the best Blofeld (Telly Savalas), the best score by John Barry, and the story (very close to the book) that really humanizes James Bond in a way no other film has done.
In a nutshell, in OHMSS, Bond falls for Tracy, the headstrong and wayward daughter of a Corsican Godfather, (one of the most lovable mobsters in all of cinema!) who pleads with 007 to tame his daughter and marry her.
Many fault this 1969 film for the absence of star Sean Connery, replaced by newbie George Lazenby. While it is a fair criticism, the movie still works overall.
If you have not seen it, give it a try.