Castlecourt Diamond Mystery

The famous Castlecourt diamonds have gone missing. Their disappearance is strange. To help sort out the mystery, eyewitness and various participants in the case give statements. Six "statements" bring forth the tale of stolen diamonds. The first statement is by the Marchioness' maid who describes the theft, introduces the main characters, and mentions the two detectives, one official, one private. The second section is narrated by "Lilly Bingham, known in England as Laura Brice, in the United States as Frances Latimer, to the police of both countries as Laura the Lady." It's not much of a surprise that Laura stole the diamonds, but was she acting alone, or was she in cahoots with someone else?