How News Corp wooed government over BskyB bid
James Murdoch's evidence to Leveson started off slowly and not very revealingly about phone hacking.
But it is becoming explosive over how News Corp pursued its ambition to buy the 61% of British Sky Broadasting it does not own.
What we have seen is emails from Fred Michel, News Corp's public affairs director, showing how he was garnering remarkable amounts of highly valuable information from government advisers about the attitudes of ministers towards the £8bn takeover plan.
A very bright light is being shone on the apparent privileged access to government of a commercial lobbyist.
And so far what we have learned from Mr Michel's emails is that - in his view - the government was supportive of the bid and the Culture Secretary Jeremy Hunt was unlikely to raise any objections to it.
I was struck by how rapidly Mr Michel appeared to be able to get information from the DCMS about a blog I wrote in September 2010, saying the media regulator Ofcom was likely to probe the deal (Mr Michel wrote in an email that Mr Hunt did not believe this was true - though it was).
We broke for lunch before we got to the crucial period of January 2011 and after, when Jeremy Hunt approved the takeover against the initial recommendation of Ofcom.
What will we learn about how News Corp won the approval of Mr Hunt and DCMS to allow the controversial deal, subject to BSkyB demerging 61% of Sky News?
It could be dynamite.