Mate in 3

The plan is to seize control of the h8–a1 diagonal, now under the watch of Black’s bishop on h8. Were it not for this lone sentinel, Qd4 would already bring the curtain down. But how to wrest the diagonal from the bishop’s grasp? The answer, as bold as it is brilliant, is to sacrifice both rooks.

In true Wartonesque flourish, in comes the key: 1.Rg7!, threatening 2.Qd4#. Black is virtually compelled to play 1...Bxg7, whereupon White offers the second rook: 2.Rh1!. Once more, Black must accept with 2...gxh1=any (declining allows 3.Qxb1#), but in doing so, the g-file is laid bare for 3.Qxg7# to swoop in — coup de grâce!

Quiz: Why did the composers station a knight on b6 — mere ornament, or quiet necessity?