Police officer number 2: the grenade clue (3/12)
Police officer number 2 has a friendly smile and an impeccable uniform, but a green grenade in his pocket betrays his imposture.
Police officer number 3: a strange scene (4/12)
Police officer number 3 is standing near a table with candles. His uniform is in order and his behavior does not appear suspicious.
The conclusion is that police officer number 2 is the imposter because of the grenade. This puzzle plays on our tendency to make assumptions based on appearances.
