After being told about a crime that recently occurred in Ponyville, Twilight decides to look into it with the help of her friend, Pinkie Pie. However, after investigating the crime scene, it seems that the evidence is pointing towards one of their friends as being guilty. Will their suspicions prove correct? Will they find a different suspect? Or will the crime remain unsolved? Regardless, Twilight is determined to prove her friend innocent, and to catch the real criminal.