They have three rules: sort the questions in advance, appear statesmanlike and do not let the Murdochs off the hook.
The 10 members of the House of Commons Culture, Media and Sport Committee will this weekend plot their strategy for next week's session before Parliament. They know their questioning of the Murdochs will come under almost as much scrutiny as the answers they receive.
They must avoid questions that allow Rupert and James Murdoch, and Rebekah Brooks, to claim that their answers will prejudice the police investigation. John Whittingdale, the chairman of the committee, will have lawyers present throughout the hearing to advise him. They are likely to steer questioning away from the specific allegations on hacking and into the territory of corporate cover-up.
Alongside the legal questions are political ones. Mr Murdoch has made clear that he thinks many of the allegations from Parliamentarians have been lies and is likely to go on the attack. But the committee intends to appear statesmanlike. The order of the day will be to arrive more in sorrow than in anger.
Mark Stephens, the leading media lawyer, said that committee members would have to work hard to avoid a "slow, tedious and painful" hearing. He said: "They [the Murdochs and Brooks] will bring a retinue of lawyers."
Questions for James Murdoch
Q. Mr Murdoch, you have gone on the record to say that Parliament was misled over the phone-hacking scandal. Can you please explain to the committee what specific information you have which made you draw this conclusion and when you received this information?
The committee is likely to use open-ended questions to try drawing information from Mr Murdoch. Even if such questions appear less hard-hitting, they will prevent him from hiding behind the police investigation. The committee will also want him to put information on the record.
Q. In a statement you admitted that News International paid out-of-court settlements to the victims of hacking – which you personally approved. You said that at the time you "did not have a complete picture when you did so". Can you tell the committee what advice you received and from whom, before you authorised the payments.
This gets to the nub of the problem for James Murdoch. He approved spending £700,000 for News International to settle with Gordon Taylor. Why did he do it? The committee will argue this information does not cut across the police investigation and will come out anyway.
Q. When you took over at News International in 2008 can you please tell the committee what, if any, briefing you had on the phone-hacking allegations and when they took place and by whom?
One of the committee's targets is Les Hinton, who ran News International at the time of the hacking scandal.
Q. Will you now widen the external inquiry at the company to examine the emails of all senior staff at the company (including Les Hinton, Rebekah Brooks and yourself) to establish what, if anything, was known about the hacking scandal and who, if anyone, authorised payment to police officers?
This request appears reasonable and would be hard to reject out of hand. MPs want to widen the inquiry as far as possible.
Questions for Rupert Murdoch
Q. Will you apologise to the victims of phone hacking right now?
This is not about information – it's about headlines. Mr Murdoch has never been big on mea culpas and these MPs would like to be the ones who change that.
Q. On behalf of the company, when did the NOTW and News International first learn there was evidence that phone hacking may have spread beyond the single "rogue reporter"?
All three witnesses are not likely to respond to this one but the committee should put the matter on the record. The point at which the NOTW and NI executives knew hacking was not confined to Clive Goodman is at the scandal's heart.
Q. When you first heard about the allegations of phone hacking what action, as the ultimate head of the company, did you demand – and do you now believe those orders were carried through? If they were not, who was responsible?
The buck stops with Rupert Murdoch and the committee has a chance to find out for the first time what he knew and when.
Questions for Rebekah Brooks
Q. You told this committee in 2003: "We have paid the police for information in the past." You then later denied this. For the record what is your current position?
We now know that News International was paying police officers – so how she answers this question will be interesting.
Q. News International agreed a settlement with Max Clifford in 2010. Were you aware of the payment and what advice did you receive about it and from whom?
Ms Brooks was appointed News International chief executive in 2009 and would have been expected to have oversight of the decision to pay Mr Clifford £1m in damages and legal fees.
John Whittingdale (Con)
Chairman for the past six years. Two months ago, he said he saw no reason to reopen investigation into hacking because "we've got other things to do as well you know". Not any more.
Damian Collins (Con)
Campaigned for investigation into Fifa corruption claims in the Sunday Times.
Adrian Saunders (Lib Dem)
An early advocate of a judicial inquiry into phone hacking.
Philip Davies (Con)
Populist Eurosceptic right-winger and scourge of political correctness.
Louise Mensch (Con)
A novelist turned MP. Recently married the manager of metal band Metallica.
Paul Farrelly (Lab)
Former journalist who tabled a parliamentary question asking about the dumping of toxic waste in Africa by Trafigura. Company tried, and failed, to ban reporting of the question.
Therese Coffey (Con)
Former finance manager for Mars and the BBC. Has a PhD in chemistry. Remarked last week that Rebekah Brooks had faced a "witch-hunt".
Alan Keen (Lab)
He and his wife Ann were dubbed "Mr and Mrs Expenses" after they claimed for a flat on the Thames South Bank despite having a home in her constituency, which was just 10 miles away.
Jim Sheridan (Lab)
Resigned as a parliamentary private secretary in 2006 in protest at Tony Blair's policy on the Israel-Lebanon conflict. Led moves to regulate gangmasters.
Tom Watson (Lab)
If anyone can take credit for exposing the phone-hacking scandal, it is him. Last year, he said, had been "pretty lonely" for hacking campaigners. Tuesday's hearing will be his vindication.