You reach 6NT and you get the 10 lead. How do you play the slam?

Suit combinations frequently have to do with "safety plays." Here's one from an out-of-print Terence Reese book, "The Most Puzzling Situations in Bridge Play" (Signet Books, 1980, p. 43):

Reese wrote: "Here the only danger was a 5-0 break in hearts. The safety play to be sure of four tricks in hearts is too rare to be in the textbooks, but it is not difficult to work out...." Have you found it?

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