The International Criminal Court sits in a non-descript suburb in what is a largely non-descript capital.  From his spacious office in the Hague, the Chief Prosecutor Luis Moreno Ocampo is the man tasked with investigating tyrants and regimes.
Neat and fastidious, he is unfailing polite even if he does carry the air of a man who would be rather doing something else when we sit for an interview.
We will meet again later today.
The Argentinean will announce "the opening of an investigation in Libya", the latest step in the growing international pressure against Colonel Gaddafi and his cohorts in Tripoli.
Mr Ocampo, at a news conference, will name names, people to be targetted in a full scale inquiry into possible crimes against humanity.  It is almost impossible to think the Colonel will not be top of the list.
As well as presenting "preliminary information as to the entities and persons who could be prosecuted", the prosecutor will "put them on notice to avoid future crimes".
Human Rights Watch says hundreds have been killed in the crackdown against the revolt which began last month, and tens of thousands of people are desperately trying to get out of the country.
Mr Ocampo only began working on Libya after the United Nations Security Council asked the ICC to establish if there were grounds for a full investigation.
It said "the widespread and systematic attacks currently taking place against the civilian population may amount to crimes against humanity, which fall under the ICC's mandate to prosecute."
In just 48 hours the prosecutor has decided there is something worth looking into.
Ocampo has cited information that forces loyal to Gaddafi were attacking ordinary people "If people were in a square and were attacked by tanks, planes and soldiers, and if people were killed in a systematic way, this was a crime against humanity," he said, promising to move "swiftly and impartially".
Talks have been going on between The Hague and the UN, the African Union, the Arab League and individual states in the investigation. Interpol will also be asked for help.
When the prosecutor has gathered the evidence he needs - he takes his case to ICC judges, who decide if arrest warrants should be issued. Getting the people into custody is much more difficult.
This is the second time that the UN Security Council has referred a case to the ICC the first, in 2005, concerned alleged human rights violations committed in Sudan's Darfur region.
That led to arrest warrants being issued in 2009 and 2010 against Sudanese President Omar al-Bashir for genocide, war crimes and crimes against humanity.
That was the last time I met Mr Ocampo. He is frustrated Mr Bashir is still free.  And that still – there is a need for someone to investigate crimes against humanity.