A £1bn High Court fight over an oil group focused on northern Iraq, which involves a former Green Beret and a tycoon who entertains contacts at strip clubs, starts on Wednesday.
In one of the most high-stake commercial battles this year, Rex Wempen, who became a business consultant in Baghdad after his career in the US forces, will say that his company, Excalibur Ventures, is owed either 30 per cent of Gulf Keystone Petroleum's Iraq assets or $1.6bn (£980m) in damages.
Todd Kozel, the colourful chairman and chief executive of Gulf Keystone, one of the Alternative Investment Market's biggest companies, will deny the claims over the course of the 12-week case.
Mr Wempen is expected to argue from the witness stand that he was the one who first identified the oil potential of Kurdistan, the semi-autonomous region to the north of Iraq.
Mr Kozel will argue that he was the brain behind the deals that have seen Gulf Keystone make one of the biggest finds the oil industry has seen in years.
The spectre of the case is thought to be a major reason why Gulf Keystone has not met its long-stated aim of jumping from the junior Aim market to the main board of the London Stock Exchange.
Also, there have been tensions between Baghdad and the Kurdistan capital, Erbil, over the legality of the contracts that the Iraqi government has signed with foreign oil explorers and producers.
Mr Kozel's last high-profile court appearance, last year, involved his $100m divorce case in Florida, when he said of one $5,100 strip-club bill: "When we do it, we take a lot of people and do it properly."