Strange Case

"Grandpa, grandpa, what did you do before?" "Baby Xiaoyue, my grandpa used to be a policeman, specializing in catching bad guys." "Wow! Grandpa is so awesome!" "Haha" "Grandpa and grandpa, tell me a story, just tell me a story about when you were a policeman." "There are so many stories... My grandpa can't even remember them." "Grandpa, just tell me! Xiaoyue wants to hear it." "Okay, okay... Xiaoyue, my dear, grandpa will tell you some interesting things." "Strange case."