Quest Objectives
When you first arrive at Paradise Falls you'll be stopped by Grouse, the gate guard. He won't just let you walk into Paradise Falls, but he will offer you the chance to gain entrance by capturing slaves. Grouse has a VIP list of slaves he wants you to catch, there are four names on that list, if you agree to capture the slaves he will give you a Mesmetron and a Slave Collar, you only get one Slave Collar at a time so you'll have to return to Grouse after each capture.
Alternatively, you can gain entrance to Paradise Falls by paying Grouse 500 Caps or by having very bad karma, the option to do the quest will still be given.
 The Slave List
The four slaves on the list are:
Before the quest starts, all four of these people can be killed if this happens, the quest will cease to exist and you'll be given automatic entry to Paradise Falls, however you will miss out on the Strictly Business Achievement. Once the quest starts Flak cannot be killed, attempting to do so will result in him becoming unconscious for a brief moment, the other three slaves can still be killed at any time. You only need to capture one slave to gain entrance to Paradise Falls but you'll have to capture everyone on the list (unless they're dead) to complete the quest.
If you've already completed the Big Trouble in Big Town quest, Red can be found in the clinic in Big Town. Simply mez her then add the collar and tell her to go directly to Paradise Falls or her head will explode. Make sure you're standing closer to the door than she is, once Red leaves the clinic and the Big Town resident see her with a Slave Collar, the whole town will turn hostile towards you. If you get out of the clinic before her, quickly bring up your Pip-Boy and fast-travel out of there.
If you haven't started the Big Trouble in Big Town quest, Red can be found in a prison cell at the Germantown Police HQ. You can simply enslave her from here, but that will stop you from completing the Big Trouble in Big Town quest.
 Susan Lancaster
Susan Lancaster can be found at Tenpenny Tower, during the day she is usually seen wandering around the bottom floor, however during the night she heads up to the Penthouse Suite, this is the best time to enslave her. Head up to the top floor and enter Mr. Burke's room, she can usually be found sitting at the desk or sleeping. Mez her, add the slave collar and tell her to run to Paradise Falls before the slave collar makes her head explode.
Luckily, everyone in Tenpenny Tower wont turn hostile, only those who are on the top level. The only other person on the Penthouse Suit level is a single security guard, kill him and you can head back down stairs without worrying about more fighting.
Arkansas can be found at the Minefield, unlike the other people on the list, Arkansas will be hostile towards you from the moment he sees you. There are two big problems with capturing Arkansas, one is that he's surrounded by over 60 Frag Mines in all directions, the other is that he wants to kill you, so simply walking up to him and enslaving him isn't an easy option. The best way to capture him is to sneak around the mines and stay away from the direction he's looking. If your quick, you can deactivate mines before they explode, if any do explode this will likely attract Arkansas attention. Once you get close enough, mez him, add a slave collar and tell him to head towards Paradise Falls. Make sure you fast-travel away from the Minefild as soon as you've enslaved him, otherwise you'll likely see Arkansas run into a mine and kill himself.
Flak can be found in Rivet City, he is probably one of the harder slaves to catch because of the huge population in Rivet City. A quick, but dangerous way is to mez him while he's in the Marketplace, there's around 20 people in this area who will all turn hostile towards you, however you are much closer to the exit, so you can simply run outside and deal with the two security guards then come back three days later when the town has calmed down.
Another way is to wait until around 2 or 3 pm when Flak will sometimes go to the ship's deck for a cigarette, there's no security guards in this area so you can enslave him and fast-travel away without any fighting.
Grouse will give you 250 Caps for each of the slaves you bring back, so there's up to 1000 Caps to be won on this quest. He will also let you keep the Mesmetron and offer you the chance to capture more slaves. He doesn't say anyone specific but there are only a select few people in the Capital Wasteland who can be captured. Grouse will reward you with another 250 caps for each slave you bring back.
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