Watson and Holmes are returning from the lock-and-key shop where they've ordered an extra apartment key because Watson lost his. As they arrive, Watson bounds up the steps to 221B Baker Street and barges into their apartment as Sherlock Holmes follows him. ""I'll show you my deductions today Holmes!"", he says. ""I can deduce too!"" Sherlock Holmes shows him the only key to the apartment and says, ""What can you deduce from this key?"" Watson examines it. He says: ""The key has a speck of dirt on it which indicates that you have dropped it once today."" ""The key looks like it's made of an alloy of copper and iron."" ""The key's edges show wear and tear which means it has been used often."" ""There is a chocolate stain on the key which means you have eaten chocolate today."" ""Amn't I awesome Holmes! What can you deduce?"" Sherlock Holmes shakes his head as he says: ""As usual, you have missed everything that is of importance. I have not inserted the only key to this apartment and yet you were able to barge right into our apartment. Our flat has been broken into!""