Cameron's direct EU referendum appeal to voters
At a hastily arranged press conference on a beautiful, if sweltering London rooftop, David Cameron made his familiar arguments about the economic risks of leaving with the added force of some powerful interventions overnight.
He said he'd decided to hold the briefing when he watched the news last night and was moved, as he put it, to go out and correct the "complete untruths" of the Outers, to ram home again his belief that they're making untrustworthy assertions about a nirvana outside the EU, while it's left to him and his panoply of global movers and shakers to put the cold hard facts.
What was so striking though was the prime minister's efforts to appeal directly to voters, urging them "not to sit it out", not to miss this "vital moment" that could "alter the country's destiny".
In other words, if you're not that bothered, please, please listen to me, and please, please turn out to vote, or else the enthusiastic Brexiteers who'll rush to the polls might just win the day.
One Remain source admitted to me they were starting to panic about the result, joining several senior figures who in recent days have told me they are seriously worried about voters who are notionally on their side staying at home.
A senior source in the Out camp suggested the polls are tightening but the fundamentals haven't changed that much. The polls were wrong of course in the general election, and have lost some of their credibility.
The widespread assumption has been that Remain will win. But as the clock ticks down that assumption is feeling pretty shaky - watching the prime minister this morning, it doesn't feel like he completely believes it any more.