It began as a tale of sex, lies and a secret video recording at the heart of the ministry charged with bringing the Elgin Marbles back to Greece.

But after two apparent suicide attempts and allegations of blackmail and endemic corruption, the affair has called into question the moral authority of the Culture Ministry as it presses its case for the return of the ancient masterpieces.

The juiciest sex scandal in modern Greek memory began when an archaeologist allegedly decided to get revenge on her married boss after he refused to give her a full-time job at the ministry.

Evi Tzekou, 35, is in custody on charges of attempted blackmail after apparently smuggling a camera into the bedroom of Christos Zachopoulos, her lover, and filming more than 100 hours of extramarital sex.

Mr Zachopoulos, the chief of staff at the Culture Ministry, jumped from a fourth-floor flat in central Athens hours after losing his job by prime ministerial order. He remains in a critical but stable condition, unable to talk to investigators.

Ministry staff claim they were privy to “ferocious arguments” between Mr Zachopoulos and Ms Tzekou, in which she demanded €200,000 (£149,000) to stop her “exposing” him after he refused to renew her contract. Ms Tzekou denies charges that she posted copies of the sex tape to media outlets.

The Prime Minister is known to have received a copy of the film last month, and journalists who have seen it say that the DVD contains “typical bedroom action” with no suggestion of political or business wrongdoing. However, ministry sources said they believed that Ms Tzekou took the sexual initiative to blackmail Mr Zachopoulos on behalf of businesses wanting to clear archaeologically listed land for commercial use.

“We know he was able to decide on declassifying archaeological land in favour of developers, and that he had made several such controversial decisions in the past,” one source said.

Media speculation that Mr Zachopoulos could be a victim of blackmail remain unsubstantiated. Last weekend, however, Heracles Koutelidas, a lawyer acting for Ms Tzekou, threw himself in front of a van, claiming that he was the victim of a witch-hunt and had been “labelled a blackmailer by the media”. He survived.

The scandal has sent the popularity of the conservative Government to record lows and has dented the prestige of the Culture Ministry. Mr Zachopoulos was a key official in the campaign for the return of the Elgin Marbles, and there is a widespread sense of shame that the organisation claiming the moral high ground for their return should be racked by scandal.

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