I Know What You Did Last Wednesday

"I Know What You Did Last Wednesday" (2003) is a short story in the Diamond Brothers series of comedy thrillers by Anthony Horowitz (author of the Alex Rider series). Aimed at children but enjoyable for all ages. Horowitz keeps the readers attention with gruesome jokes and spine tingling drama.

The plot bears a close resemblance to Agatha Christie's And Then There Were None, where visitors are invited to an isolated island and begin to get murdered in ways that are close to some sort of code or guide. The title is a parody of "I Know What You Did Last Summer".

The main characters are Tim Diamond, an incompetent private detective, and his smarter younger brother Nick, who usually solves all of Tim's cases. Narrated by Nick Diamond, the book is short and fast paced.

Plot summary

The Diamond Brothers receive an invitation from Tim's old school friend Rory McDougal. It invites them to Crocodile Island for a high school reunion. With the promise of £1000 for going, the broke Diamond Brothers decide to go.

There they meet Sylvie Binns, Janet Rhodes, Libby Goldman, Brenda Blake, Mark Tyler and Eric Draper (Tim's old classmates). Only one classmate is not present, Johnny Nadler.They are taken over to Crocodile Island by Captain Horatio Randle Captain of a small boat named the Silver Medal.

Upon arriving on the Island, they find Rory quartered. With the boat not returning for 3 days, and all phones signalless, the group have a murder mystery on their hands. They proceed to search the island, discovering no-one. Later in the same day Sylvie is poisoned. Paranoid, the group begin to distrust each other, and agree to do everything in twos. However, this does not stop Janet Rhodes from being stabbed by a model Eiffel Tower, or Libby Goldman being hit on the head by a Globe. Both cases are fatal.

With just five of them left, the group agree to stay in the hall and watch each other. The lights go out, and when they come back on, Brenda Blake is dead, by an organ pipe on the head, and Eric Draper from a old fashion pistol, which lies smoking on the floor. Mark Tyler is missing, but discovered outside, impaled by a Javelin.

Tim becomes paranoid and accuses Nick as the muderer and runs for his life towards the cliffs. As he does, the cliffs collapse beneath him, and he falls down to a bed of rock "needles".

Captain Randle arrives, where Nick deduces that the Captain is actually called Johnny Nadler, the perpetrator of the murders. He explains his motives, he was always second place, first at school, where he came second in all subjects, and then in life, second place with patents, etc. He traces it back to his time at school, and sets up cunning traps to kill them all appropriately.

Rory, 1st in Maths, was "divided". Sylvie, 1st in Chemistry was given a Poisonous substance. Janet, 1st in French was killed by a model Eiffel Tower. Libby, 1st in Geography was killed by a model Globe. Brenda, 1st in Music was killed by an organ pipe. Eric, 1st in History, was shot by a old pistol. Mark, 1st in Sport, was impaled by a Javelin. And Tim, 1st in Needlework, should die below.

Johhny is about to kill them both, but then in the nick of time Eric Draper hits him with a blunderbuss. With the shot not being fatal, the Diamond Brothers and Eric sail the ship back, with Johnny tied up.