Shrouded in mystery, the great detective began his search for evidence. He checked his device, found out what time the message was received and factored that versus the projected time of the shooting.
Was the smiley face a clue or a red herring? The one thing that sets Sherlock apart from other famous detectives, like that hack Tracy and that moustachied little Frenchman Poirot, is his uncanny ability to see inside the minds of the criminally insane.
How did he acquire such a strange gift? He was more than a little mad himself!