It seems Lukan and his half-ogre comrades are charging a toll from anyone who wants to cross the bridge. There are four ways to get past them:
a) You can pay the toll (1000 gold), although it's probably more than you can afford.
b) You can circle around Lukan and steal his key to the gate.
c) If you didn't accept a quest from Constable Owens to get rid of the thieves, you can get a quest from Lukan to destroy the bridge materials down the coast to the south (#13). If you do that and return, you'll earn 1000 experience but lose alignment, and Lukan will give you the key to the gate blocking the bridge. Lukan will also tell you about the Thieves Underground and suggest you might be able to learn more about it in the taverns of Tarant.
d) If you have at least 1 rank of persuasion, you'll get the dialogue option, "I may be able to persuade you otherwise." Then pretend to be with the Thieves Underground, but avoid talking about leaders and handbooks. You'll be able to convince Lukan that he's encroaching on someone else's territory, and he'll be so anxious to leave that he'll give you 200 gold. You'll also earn 800 experience and a fate point. Now if you want, you can kill him before he leaves (see below) and earn another fate point that way.
e) You can kill the thieves. If you're a pure melee character, you can probably defeat the thieves without any problem. For other characters, it's probably easiest to use some of the explosives found in the Crash Site Cave. Even if you have no throwing skill, you can still use the grenades, but you might completely miss the thieves. So save first and then try attacking them, and load if necessary. If you can hit Lukan with an explosive grenade and one of the half-ogres with a stun grenade, you should have an easier time with the battle. You should definitely kill the thieves if you're a half-ogre, or if you're planning to add one to your group. Both half-ogre thieves have large leather armor, and there aren't many places where you can find large armor.
