Spoiler warning: this text details events which occur in Tiassa
Dathaani is a member of House Jhereg who became interested in undertaking a plan to assassinate an enemy of the Organization, Vladimir Taltos. He has curly brown hair and sharp eyes. He often thinks of himself as a reincarnated Yendi, and does not care too much about the financial rewards. He worked for Rynend.
The most elaborate part was locating him, which he took care of by managing to convince the Empire that the Jenoine were about to invade, which set off alarms, an evacuation, and expenses, among other things. This news, together with the information about a mysterious object which may help against the Jenoine in the hands of Vladimir was enough to convince Zerika to locate him. It is notable that despite the leverage of the plan, it does have problems. Firstly, Dathaani employed a Hawklord to tell the Court Wizard of the Empire rumours about the object which is easily tracable, but it is possible Dathaani wasn't terribly concerned about his own safety and decided to risk it. Second, he used the Imperial representative of House Jhereg to request to be a witness to the performance of the spell, which was legal and, furthermore, irrefusable, but suspicous. As it were, it turned out the second part of the plan allowed opposing parties to neatly identify the whole thing as a possible conspiracy; the Hawklord was probably safe.
Most of his resources probably went into the actual forces at work in making the Jenoine threat seem real. He contacted Lady Cheoru in the Left Hand of the Jhereg for the job, which cost him a thousand Imperials. The sorcerous work turned out to be convincing. After, he decided to arrange for five muscle to counter the target's familiars instead of a professional. His activities during the operation were inside an inn called Antlers in Newalter and Slate.
Daro was, perhaps subconsciously, suspicous, and decided to follow up on her feelings by meeting her son, who had a minor involvement with Vladimir in the past. She checked whether or not Lord Faorie still had the tiassa based on her knowledge of these events, and found that it had been stolen from him by a male Easterner, of which there are strictly limited number. Her next move was to Cawti's home, which turned out to be helpful because Cawti had an idea of what might be going on which complemented Daro's feelings well. Thus, the three: Daro, Cawti, Norathar, met with the Empress and agreed to set a false location then meet the assassins. The deed was done, confirming their suspicions, but not giving them any further information. Norathar used some of her former contacts within the Jhereg to find out more. Her sources led to both a man named Rynend whom the Jhereg Council gave the job and Shribal who is rumoured to want to assassinate Vladimir. They checked Rynend first because their influence would be greater on someone close to the Council, for some reason. Norathar and Rynend talked for a bit, and worked out the following comprimise: Norathar would not inform the Empire about Rynend's involvement and Rynend informed Norathar the planners name and possible location, which actually does not fail the agreement he made with Dathaani.
Eventually, Daro and two Phoenix Gaurds and Norathar and Cawti converged on Dathaani separately. He was trialed and starred, which probably means he was charged of treason.