First time I saw it, two Rooks on h-file, hmm, we need get rid of the g7 pawn. Immediately one candidate move, Qxg7+ to open the King. Kxg7, Rh7+, Kg8, Rh8+, Kf7, ah, the King escaped. Not good.
OK. Let's refine it, Rh8+ first, Kf7, Qxg7, now King can't go e8, so Kxg7, R1h7+, Kg6, hmm, no mate?! I spent half hour on following through this idea, but got nowhere.
Now we returned back to square one.
Pawn g6 might work if black Queen is not there.
How about white Queen go Qe5? A crazy idea, but black can't do Qxe5, g6 will force a mate on h8. xe5, Nxe5, now either Knight guards f7 or Pawn g6 will guard it. A perfect plan! But wait, black has no need to take the Queen. He can just move Rook over to protect his Queen. So close!
6th rank is critical, so is the a2-g8 diagonal. How about Qc4? d5 intercepts, still not good.
How about g6, Qxg6, Ne5, xe5, Qc4+, will lead to mate in next move? But on the second move, black instead will take the Rook, Qxh5, Rxh5, then xe5. White is winning with QRN vs RRB. Anything better?
Let's switch order, g6, Qxg6, Qc4+, d5. Now e5 square has no protection. Ne5 will force a mate. Finally we have distracted two defenders, and reached a mate.