I've been working on techniques to develop idea-hooks. I think the foundation tools are there but I haven't found a way to make them consistently work as a whole.
A television broadcasts TV from the past and the future
A family turn on their TV and see that the programmes featured are from ten years ago. They switch their TV off and on again and find that this time the programmes on are from forty years ago. They keep changing channels but all the programmes are forty years old. Once again they turn the TV off and on again, but this time find a news programme is on, but the news programme is from a year into the future.
Future criminals punished with "Groundhog Day" from hell
In the future, the punishment for offences involves the guilty experiencing bad events from their own life repeatedly. So, if they accidentally ran over their Gran's cat they experience that event (and the emotions) many times (the amount of repetition depending on the severity of the crime).
Perfect recall aids retrospective crime investigation.
In a kind of Minority Report in reverse, scientists find a way to stimulate the brain so that a person can visualise events from their past in 20/20 vision. Used as a crime prevention measure, the procedure can be carried out on any individual to make them visualise any crime they have witnessed in the past -- be it a minor crime such as speeding, or a more serious crime such as murder. Eventually, technology finds a way to project the image on a screen. With an image featuring a crime such as speeding, the police can even calculate the speed of the vehicle.
Foolproof disposal of corpses
A device is created that can compress a corpse into a small, disposable cube. A group of police come into possession of the device and decide to act as judge, jury and executioner in crime prevention.