Inna Gudavadze, the widow of Georgian oligarch Badri Patarkatsishvili, has hired the PR company to help create political pressure around her legal battle to secure her late husband's assets.
In May, Ms Gudavadze's lawyers met in Brussels with the EU's special representative for Georgia and with senior officials in the European Commission to discuss Imedi TV.
The Patarkatsishvili-owned TV station was taken over by his step-cousin, Joseph Kay, last year on the basis of a contested will, sparking a legal challenge in the Georgian courts.
Imedi used to be the Georgian opposition's main TV outlet. But since the takeover it has stopped broadcasting anti-government material, such as footage of masked men beating up opposition protesters at night.
The Georgian government says it has no interest in the case, which it calls a "family matter." But Ms Gudavadze's lawyers and APCO briefed EU officials that the government is leaning on judges to quash her appeal.
"[APCO] is quite a powerful consulting firm. They seem determined to push it forward. They seem determined that only a decision at political level will solve it, not at judicial level," one EU official told EUobserver.
The European Commission said the Georgian government has already taken over two Patarkatsishivili assets, an amusement park and a bank. It has also tried to wrest control of his mineral water company.
The size of the fortune alone makes it politically significant. Mr Patarkatsishivili's worldwide assets are reportedly worth up to €8 billion. For comparison, Georgia's post-2008 war reconstruction package is worth €3 billion.
Brussels is concerned about Georgia's general respect for the rule of law and free press. But it has refused to get involved in individual legal proceedings so far.
Meanwhile, APCO's pro-Gudavadze work poses questions about the company's profile.
The PR firm has close ties with the US state department and has in the past lobbied in Europe on behalf of anti-Kremlin reformers. But the Gudavadze campaign paints the anti-Kremlin Georgian leader, Mikhail Saakashvili, in an unflattering light.
"APCO does not take clients on the basis of 'who' we are for or against," the company's deputy managing director, B. Jay Cooper, told this website. "We are not anti-Russia, nor are we anti-Georgia. We are pro-rule of law."
The Berezovsky connection
The Gudavadze campaign also links APCO with Boris Berezovsky, a Russian media tycoon living in London and wanted in Moscow on charges of fraud and money laundering.
APCO says it has no commercial or informal relations with Mr Berezovsky.
But the Russian is a former business partner of Mr Patarkatsishivili and a one-time friend of Ms Gudavadze. He is also fighting to discredit the Joseph Kay will and the Georgian government in his bid to claim a share of the fortune.
"Saakashvili behaves like a dictator," Mr Berezovsky's advisor, the British PR guru, Lord Bell, said. "Mr Berezovsky is interested in promoting democracy around the world. He would like to see a free and fair election in Georgia."
For its part, the Joseph Kay camp has accused Mr Berezovsky of using dirty tricks to erase the contested will, adding another twist to the tale.
The US lawyer who put forward the Kay will, Emmanuel Zeltser, on 12 March 2008 flew to Belarus, where he was arrested on charges of carrying forged documents.
Mr Zeltser was jailed for three years in a behind-closed-doors trial and last week started a hunger strike to protest his innocence.
Dinner is served
His brother, Mark Zeltser, alleges that Mr Berezovsky had dinner with Emmanuel in London on 11 March 2008, duped him into flying to Minsk on his private jet and set up the sting together with his old friend, Belarus President Alexander Lukashenko.
"Berezovsky needs big money in order to play international politics," Mark Zeltser told this website. "The easiest way is to grab the money of his friend and long-term business partner [Mr Patarkatsishivili]."
Belarusian diplomats and Mr Berezovsky's people have poured scorn on the account. "It's utter tosh," Lord Bell said.
Meanwhile, Emmanuel Zeltser is becoming "very thin" as well as suffering from diabetes. But his fate is not high on the EU's list of concerns.
EU external relations commissioner Benita Ferrero-Waldner in Minsk on Sunday urged Mr Lukashenko to release all political prisoners. But when asked about Mr Zeltser by EUobserver, her spokeswoman said only: "I have read about him on the newswires" and declined to classify him as a "political" case.