As a detective solving the mystery of the crossword clue ‘Plays a Halloween prank on, in brief’, the first thing I noticed was the phrase ‘in brief’, suggesting that the answer should be an abbreviation. Halloween is often associated with pranks and mischief, so I assumed the answer would be a term related to these aspects of the holiday. As I thought about common Halloween pranks, toilet papering (or TPing) immediately came to mind. However, ‘TPing’ is five letters, so it couldn’t be the answer. Then it hit me – TPS is a commonly used abbreviation for ‘toilet papering someone’s house’ (or TPing for short) in the context of online messaging and social media. From there, it was clear that TPS was the answer to the crossword clue.