In the magnificent Norwegian thriller Headhunters, Roger Brown is a management headhunter who moonlights as an art thief to pay for his expensive support for his beautiful wife who he is afraid of losing.
Claes Greve poses as retired businessman with the qualification to take a vacant job Roger is doing a search for (Claes' purpose is industrial espionage). But he also claims to have an original long-lost Reubens' painting inherited from his mother. Obviously Roger wants to steal it.
When I originally watched the movie I assumed Claes was so smart he knew Roger was an art thief and invented the missing painting story to trap him into doing what he wanted. But on rewatching, there is a more straightforward explanation: the story was designed as an excuse to meet Roger's wife who will introduce Claes to Roger and therefore the recruitment process for the vacant job.
So did Claes know Roger was an art thief? Or was the art merely a ruse to get an introduction to Roger via his wife