He's an international jewel thief trying to catch another international jewel thief!  She's a museum... employee?  Evidently?  It's All for Quinn by Kay Hooper, a Loveswept that's also somehow fourth in a series with real continuity and the expectation that you have read the others! And yes, the cover on both Amazon and Goodreads is just a photo of the book somebody took with flash.

It's caper time!  No serious triggers in this at all, just good ol' caper stuff like chloroforming and Interpol.