Free Ghoul prisoner

 is a side quest in the original Fallout.

Walkthrough
In the Watershed building of the Watershed area of Necropolis, you will find some prison cells just down from the Water pump. A ghoul is trapped in one of them. Unlock the cell and ask him where the Water Chip would be being kept. Conveniently, the entrance to the Vault where it resides is right next to the Ghoul's cell. Let him leave to recieve experience.

Reward

 * 500 XP.