Michael Winner, a friend of John Cleese, is reported to have said that if anybody marries Cleese's recent ex-wife they had "better have a prenuptial agreement".
(Actually, with her divorce settlement it is she who needs a really good prenuptial agreement!)
I expect this is based on the reports that she has obtained a massive financial settlement from him which obliges him to pay millions up front to her plus keep working sufficiently to pay her £600,000 per year until he is 72. John Cleese himself apparently says (and was he only half joking?) "I start to wonder how much it would have cost me if she'd contributed anything to the marriage".
I am aware that John is previously well known for settling divorce cases without unpleasant disputes but not this time.
A prenuptial agreement would certainly have been likely to save him some £millions. Such an agreement was often ignored as the Courts didn't keep to them but now they probably will as you can read in this Blog.