Ambiguous Situation: The episode ends with the reveal that the Mona Lisa in the Brakenreids' home, presumed to be a copy, has the exact marks that the Louvre's telegram says indicate the real one. But the Louvre never saw the copies, and it's entirely possible a good forger would have included them.
Continuity Nod: Inspector Brakenreid's interest in painting is referenced again, with him giving Emily Carr advice and being one of the few characters who had heard of the Mona Lisa before it was stolen.
Brackenreid encounters Emily Carr at the bar. She helps out with the investigation and later gives him a sketch of her famous "The Indian Church" painting.
Vincenzo Peruggia, the actual thief of the Mona Lisa, manages to avoid becoming too embroiled in the investigation and is able to skip town with the (or at least, a) Mona Lisa, so he can be arrested two years later when he tries to sell it in Florence.
Replaced with Replica: The sold Mona Lisas. Station House 4 ends up with three seemingly identical paintings, without any way to tell them apart until the Louvre's telegram arrives.
