The Christmas carol "Do You Know How Christmas Trees Are Grown?", sung by Nina, was written for this film (sunshine and rain drops, in case you didn't know). Most of this film takes place in Switzerland at a place called Piz Gloria, an arch villain's lair fronting as an allergy clinic. Identify this film that sees our hero, played by George Lazenby, get married, only to see his wife murdered shortly after on the orders of Telly Savalas' character.
On Her Majesty's Secret Service (OHMSS)