This will launch the Kidnap For Ransom event and select your Kidnapper spot/Residential lot if wanted. Once you have your target use the Hostage social menu and select Kidnap For Ransom.
Then kidnap them for ransom and take them back to your kidnapper’s spot. Get them chatting and sneak off somewhere private. The other method is to visit a community lot and select someone at random. Then have your kidnapper visit them and spring a surprise kidnapping.
You can create them in CAS and place them on a lot. Now find a hostage to start earning money. Lastly, you’ll need a fridge to feed the hostage. Add a desk, chair, and computer for your communication needs. This spot can be a basement or someplace where you won’t be found. The first thing you’ll need as a kidnapper is somewhere to take the hostage and communicate with the people who’ll pay their ransom. This mod adds functional kidnapping to The Sims 4.