1NT 15-17. 2H Michaels. 3H a good raise (probably in spades) and shows short diamonds as no double.
West is a very good player who will try and play the contract as often as possible. Everyone knows he didn't intend 3D as a transfer break, but as showing diamonds.
East is noticeably weaker, but not absurd. East will usually signal count/attitude religiously, West may not bother
Ace of diamonds lead, on which East plays the 8 (reverse attitude/standard count)
West thinks for a while, and switches to the queen of cubs.
Plan the play.

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IMO you hope the full deal is something like this.
LHO probably has six good diamonds. Otherwise, his three-level foray would be foolhardy.
You want to ruff two diamonds in dummy without being over-ruffed, so you want LHO to have ♠KT.
You need RHO to hold at least one heart honour. It may not matter which, but on previous assumptions, he should have the ♥A.
There seem to be several successful lines on this layout. For example,
You can take ♣AK, ♥K, two ♦ ruffs with ♠J8, and five more trump tricks.