We get the latest on the prime minister's future from Henry Zeffman - as business secretary Peter Kyle tells the BBC that Keir Starmer is 'reflecting on political reality'. Dame Mary Beard draws parallels between the politicians of today and those of the classical world, and we get advice on political instability from Italian journalist Beppe Severgnini.
Also, we mark the moment of the summer solstice with Scotland's astronomer royal, Professor Catherine Heymans; Frank Gardner talks about rare butterflies, and we review the papers with journalists Joey D'Urso and Stephen Bush, and TV presenter Kirstie Allsopp.