1.Bc6
1...e6 2.Qb8 e5 3.Rb7 any 4.Rxb2+ Qxb2+ 5.Qxb2
1...e5 2.Qe6 any 3.Bd5 any 4.Bxa2+ Qxa2+ 5.Qxa2
1...exd6 2.Re7 d5 3.Sd3 e1Q 4.Rxe1 B any 5.Rxc1
In Turton doubling a rook or bishop plays a critical move across a square to allow a queen to move to the square then along the line in the opposite direction, supported by the weaker piece. Here in two variations we have Loyd-Turton doubling, first shown by Sam Loyd in 1856, where the stronger piece plays the critical move. The by-play variation is beautifully worked in.
Ravi Shankar: A fine problem! Finding the third mate is the key!