West leads K and continues with the Q which east overtakes and leads a 3rd heart which you ruff high and west discards. It seems on the surface that the contract depends on the spade finesse, okay let's start by drawing trumps, they are 3-1 with east having three.

Well it won't harm to take 3 rounds of diamonds to isolate the menace and west shows 5 leaving him with one now as he threw one on the 3rd round of hearts. This is the 4 card ending

AJx
None
x
None

Kxx
None
None
J
Play the last trump West must throw a spade to keep the last diamond so throw the diamond and play K & A
You just dropped East's doubleton Q
!Well played!