Luella Price is the violent leader of the Rat Gang introduced in the first issue of Dishonored: The Peeress and the Price and the story's main antagonist. She wants to bring anarchy to Dunwall in order to seize its rule.
In the wake of Delilah's overthrown reign, Luella formed the Rat Gang to impede the renovation projects initiated by Empress Emily Kaldwin throughout Dunwall. She wants a return to the chaos wrought by the previous ruler, judging a reforming of Dunwall as unnatural. To do so, she started to murder gruesomely the rebuilding teams. She enjoys violence and chaos and does not hesitate to apply them to meet her ends. She is also aware of Emily's powers and knows how to negate them.
Dishonored: The Peeress and the Price
A few months after Delilah's reign, Luella Price left a worker alive to witness her third slaughter of the rebuilding teams. Acting this way, she hoped to encourage Emily and Corvo Attano to investigate her string of murders. Leaving enough hints to lead her opponents, she then prepared a time bomb at Dunwall's Clocktower, rigged with a swarm of special bonecharms to sap Emily's powers.
Meanwhile, Luella abducts Archibald Wainwright, an active politician advocating a democratic rule on Dunwall and the rest of the Empire. She roughs him up before explaining her plans of an anarchic rule. Archibald is smart enough to see that what she really wants is chaos so she can continue her criminal activities with ease. She then forces him to participate in her plans by gaining the people's voice.
As Archibald tried to control a crowd outside Dunwall Tower, Luella threatened him from within the crowd into instead inciting a riot. She used the riot as a distraction to set a bomb at a shelter being rebuilt, killing more innocents.
Emily Kaldwin interrogates members of the Roaring Boys Gang and learns that they've been selling the Rat Gang parts for their bombs, directing her towards an abandonned wharf at the end of the waterfront. Luella laid a trap from the Empress, greeting her when she arrived at the wharf with several of her men. Emily's powers once again turned on her, sapping her strength, and allowing Luella to beat her to the ground.
Luella explained that a dying scholar at The Academy of Natural Philosophy helped her reverse the void energy of a bonecharm which would weaken those that try to use supernatural powers in close proximity to it. She proceeds to tell Empress Kaldwin that she will finally experience the weakness everyone else lives with constantly in her final moments of life. Emily Kaldwin proceeds to defeat Luella and all her men using just her physical combat skills without tapping into her powers. She assures Luella that Emily muses on her weaknesses and how to prepare for them all the time before taking her captive.
Dragged before the Empress' Court, Luella refuses to apologize for her crimes, saying that she did abhorrent things to obtain power just like everyone else has and will continue to do, then demands the Empress get her execution over with. Instead, Emily Kaldwin decreed that Luella's life would be spared and instead her fate would be placed in the hands of a tribunal, advising a punishment of a lifetime in prison and countless hours of labor rebuilding Dunwall.