Lucky Number Slevin is a fantastic genre bending movie with a strange blend of thriller-crime-humour. And it has an excellent twist which I won't reveal for those who have not seen it (but it is the sort of movie that repays multiple viewings even though you know the twist second time around).
One part of the movie requires the protagonist to procure a body for use in a "kansas city shuffle". The reason for the need for a body is explained but the events that transpire (planned by the protagonist and his associate) render the given explanation somewhat redundant. So for what possible reason did they actually need the body given their actions negate the explanation they gave to the other characters?