Star Wars: Knights of the Old Republic/Undercity

Having killed the rakghoul that chased Hendar to the Outcast village gate, you can explore the remainder of the Undercity safe in the knowledge that you can return to the village at any time.

The Search for Bastila
Regardless of which direction you move, a blue Twi'lek female you might have seen and spoken to before in Javyar's Cantina comes running towards you from the northeast:

You can be unhelpful:

You can continue to be unhelpful:

You can speak to her again:

However, you won't be able to progress with the search for Bastila beyond a certain point without her, so it's best to choose the following response the first time you speak to her:

Once she's added to your party you can remove her again immediately, although since you don't have to remove anyone for her to join at this point and you cannot find Zaalbar without her, it makes sense to keep her unless you're playing without any party for the challenge. Otherwise:

An extra gun is always welcome and her skill with Demolitions will come in useful in the Undercity and Lower Sewers. However, you should probably find Zaalbar before exploring the Undercity much further.

Lower Sewers
The closest entrance to the Lower Sewers is to the northwest, in the corner on the right. You can get to it without any encounters, and a pile of rubble just before the entrance can be searched for random contents.