The first thing to note is that if it were Black's move, he would be dead immediately: any rook move on the c-file allows Nd6 mate, while a rook move sideways is met by Qc5 mate.
The next thing to spot is that White has no way to keep his queen and knight within range of those mates. Most White opening moves are met by a rook move threatening a check that lets Black survive beyond move four. The solution is wonderful: 1.Nd8! Rd6 (to stop Bd5 mate) 2.Bc6! Rxc6 (or 2...Rd2+ 3.Qxd2 Kc5 4.Qd4 mate) 3.Nb7!! reaching the diagram position with a bishop less. But now it is Black's move, and he must allow mate.Reuse content