Based on a Rudyard Kipling story, it is full of exotic locates, adventure, and such warm humour, under the master John Houston's direction. Houston had this in mind originally for Clark Gable and Humphrey Bogart (not to knock them, but total miscasting), then later was going to do it with Butch and Sundance (Paul Newman and Robert Redford in typically Hollywood style of going for names rather than perfect actors for the roles). Fortunately, Newman had the insight to pass on it and suggested going with the pairing that was absolute perfect as Danny and Peachy.
Caine had showed as Bromhead in Zulu, that he had the proper mien for a man in a red coat and pith helmet, and we know Connery can do anything given the crack. Since both are personal friends off screen, their on screen charisma comes is amplified by the fact the two men who actually like each other, giving good foundation in which to bring Danny and Peachy alive.
Danny and Peachy decide they have had enough with soldering for the British Empire and think it a marvellous idea to go forth into the world and find a forgotten corner and create their own,and the most forgotten place they can find on the map is Kafiristan. There they plan to become rich as kings. It is a super adventure getting there, but after the reach the small country, the lark turns into something more, with Danny taking being King Quite serious.
Look for a cameo of Mrs. Caine playing the woman to wed Connery.It just does not get any better than this, with fine fine acting, writing and directing. Just have a hankie near for the ending.