Benjamin Netanyahu will try to persuade the courts this week not to indict him for corruption.
Israel's longest-serving prime minister says he's the victim of an orchestrated witch-hunt and will deny wrongdoing in the pre-trial hearing.
Netanyahu's political survival also rides on the outcome.
He has failed to win a clear victory in two elections this year.
He's been asked to form a national unity government -- but his main rival, Benny Gantz, says he won't serve under a premier facing indictment.
So what are the allegations?
Netanyahu faces three cases.
One alleges that he granted regulatory favors to Israel's top telecoms company, Bezeq, in return for positive coverage of him and his wife Sara on a news website Bezeq owns.
The charges: bribery, fraud and breach of trust.
Second up: accusations that the couple received gifts such as champagne and cigars from a prominent Israeli Hollywood producer, Arnon Milchan, and Australian billionaire businessman James Packer.
Fraud and breach of trust are the charges there.
Finally, Netanyahu is suspected of bargaining with the owner of Israel's best-selling daily paper -- Yedioth Ahronoth -- for better coverage.
In return for legislation hampering the growth of a rival publication.
That one carries fraud and breach of trust.
As for the purpose of the pre-trial hearing: it'll give Netanyahu's lawyers a chance to argue against the charges and try to convince the attorney-general to scrap or reduce them.
He'll hear the arguments and decide whether to go ahead with his plans to file the criminal charges.
If Netanyahu is indicted, it could be months till the trial begins.
He might seek a plea deal instead.
Netanyahu isn't legally obliged to quit as prime minister unless he's convicted and he can stay in office throughout legal proceedings, including appeals.
His supporters in parliament are also trying to gather lawmakers behind granting him immunity.
Potential sentences though are steep.
A bribery conviction could send Netanyahu down for up to ten years, while fraud and breach of trust carry sentences of up to three years.