Monk keeps getting roped into things.
Even absolutely refusing to attend a wedding with Natalie as her date (bringing Disher into the picture) Monk can't stay away when Disher is the victim in a hit and run.
And the body of a blackmailing photographer is discovered in the spa.
Monk pulling a stripper in to help with the investigation and refusing to believe he's a stipper for a while actually [i]is[/i] in character -- he's proven to be very naive in the past.
But his initial refusal to attend a wedding is not well explained -- nor is his subsequent acquiescence. And Natalie's mother's imperious nature is not sufficiently "earned," so to speak. I didn't get the sense that anything significant changed in her when she decided to put the photo of Natalie and Mitch on the piano.
Monk's hijinks are funny as always, but the story isn't up to the standards this show has achieved recently. The bride wasn't sufficiently menacing, there was too much lampoonery in getting Disher to the scene, and too much cruelty in Monk pulling Julie onto the stage to recite a poem she might not be ready with.
Structurally, it was an OK mystery which is generally sufficient.
But the story they wove onto that frame was not up to standards.