This article has been updated to reflect recent events.

Stormy Daniels and Donald Trump appear to be vying for the world record for the longest one-night stand in history. Ms. Daniels, the porn star, says that she and the president had sex one time in 2006 — an encounter that may turn into a long-term relationship with the help of the California courts.

Ms. Daniels seeks to set aside a nondisclosure agreement she signed just before the 2016 election — which granted her, among other things, $130,000 for the promise to keep her mouth shut about the relationship — so that she can tell all about the liaison free from the threat of enormous damages that the hush agreement purports to impose.

Her legal position, in brief, is that the agreement was never formed because the parties never actually came to an agreement. It’s an unusual argument that would normally seem to be a dead loser because few lawyers fail to stitch up the basic requirements of a fairly simple contract such as this one. But it turns out that Mr. Trump and his lawyer Michael Cohen — who himself now has to have a lawyer to represent him in the matter — have blundered their way into giving the argument a strong prospect.

All this was before Mr. Cohen went from hot to boiling water earlier today with the announcement that the F.B.I. had raided his New York offices. According to The Times, his maneuvers in the Daniels case formed part of the legal basis for the raid.