You kidnap your neighbors. It's a pretty simple concept.

To start:
Create two sims. One should have social traits like charismatic and friendly, and they bring the sims into the prison. The other should be the one who keeps the prison in order and has traits such as neat and natural cook. Build a prison. It could be a basement or a tower or random rooms scattered around the lot. But it needs to have individual rooms which each hold: a cheap bed, a toilet, a sink, and a dining table. Each room should be isolated from the rest of the building/lot and only accessible through a door. There should also be a prison kitchen and some beds for the two prison keepers.

Imprisoning Sims

First, invite some neighbors over. Have your friendly sim chat with them a bit. Then make the friendly Sim go into one of the prison cell rooms, and call a guest over. When the guest is inside the room, then click on the door and lock it to everyone except your household. Voila! A prisoner.

Caring for Prisoners
Now, what you don't want is for prisoners to die. They have no access to food, so what can you do? You can have your other prison keeper with the cooking trait cook a meal, then place it in the guest's room. To make a single-serving portion, you can have your sim grab a plate, but not eat the meal, then drag the meal into the cell onto the dining table. Or, to make your life easier, you can make big cells with multiple prisoners and just lock the door to whoever enters, and not everyone except you, then place the meal in there and "call guests to meal". Feed prisoners once a day. If you notice one complaining of starvation, feed then immediately with a quick meal using the single-serving method.

Points

-Every prisoner you gain +50
-Every prisoner who dies of something besides old age -60
-Every Sim younger then young adult imprisoned +150
-Every escaped prisoner -70
-Every child had with prisoner +60

Other Rules:
-money cheats allowed
-you can build recreation areas for prisoners, so long as they cannot leave their building.
-Challenge ends when a prison keeper dies. After that, count up your points. If there's more than 500, If there's way more than 500, amazing job

Questions, comments? Please reply and give me feedback!

EDIT: Whoops! I recently found a similar challenge posted earlier than mine. It was totally unintentional and was not plagiarism. I am going to keep this up for now, but if the other user requests it, this will be removed.

lol.....

This is hilarious, I'm definitely going to try it out but I might take the longest time making the prison! I'm torn making a prison that looks like an actual prison or a mansion with a creepy basement/secret that lures people in with my very handsome/gorgeous charismatic sim. I'll post pictures soon! you should too!

I'm thinking of adding extra challenges for myself that would be a good add on to the challenge like you can leave out the workshop from moonlight falls or make gardens they can tend and create things that you can sell and you get extra points!

I try the challenge but when I capture my prisoners, they auto-teleport themselves outside my cell and go home...
how should I remove the auto-Teleport from them??? or it is built on the game??? >_<

That is weird. It happened to me with one prisoner, but the other two stayed. Just try a couple more times I guess.. sorry

I just started this challenge I used master controller to add the prisoners as room mates so they don't teleport out. =]

I'm going to give it a go. Looks like a lot of fun

They keep teleporting out

Add the prisoner to your house so he/she doesn't

I made an asylum/secret laboratory for my Dr Jekyl Hyde and set it up as apartments. After they all filled the rooms my sim locked the front gate! They aren't teleporting anywhere. I do have university and they are now residents in the sanatorium.

It doesn't count if they auto teleport out right? because that would ruin the challenge if they all got out like that. it would be worst if you had a dinner party, inviting like 10 sims over, a few with their kids, then you get them all into their cells, an easy 1000 points or so right? nope they all just went home by some miraculous magic trick *teleportation*
also when I invite people over since theres a good point bonus for kidnapping kids I generally have my friendly sim stalk outside the school to find a few targets before heading back home to wait to call them over.