At a cabinet meeting on Thursday morning after another night raid, Churchill joked that bomb damage to the Admiralty had improved his view of Nelson's Column. Behind the joke, Churchill was troubled that German bombers had again reached London with almost no interference from the RAF, showing how effectively darkness still protected the Luftwaffe.

That same day, Professor Frederick Lindemann, the Prof, sent Churchill a report meant to offer encouragement. He described tests of anti-aircraft mines in which tiny parachute-borne bombs were dropped in aerial "curtains" by RAF planes, and he claimed they had probably destroyed between one and five German bombers. But the evidence was weak: the action had taken place over the sea, there were no eyewitness confirmations, and no wreckage had been found. Even so, Lindemann pressed the most optimistic interpretation.

On Thursday, April 24, Mary Churchill hurried back to Chequers from volunteer work in Aylesbury, took tea with Fiona Forbes, and then rushed with Fiona to London. Delayed by calls, telegrams, and a conversation with Churchill, Mary barely managed the bath she had anticipated before going out to dine at the Dorchester with Eric Duncannon, Fiona, Mary's sister Sarah, Sarah's husband Vic, and other friends. Mary's feelings for Eric were strong enough that she recorded them in her diary in French: "Oh tais-toi mon coeur."

After dinner, Mary and her companions went on to a club party and danced until four in the morning. Mary and Fiona returned to the Annexe at dawn, and Mary called it "a completely perfect party." The next day, while resting at a friend's country house in Dorset, Mary read Alice Duer Miller's poem The White Cliffs, about an American woman who loves England deeply after personal loss in war. The poem moved Mary to tears, linking her romantic happiness to the larger emotional stakes of Britain's struggle.

In London on Friday, John Colville attended his RAF medical interview. He passed all the tests except eyesight, where he was judged borderline, though he was told contact lenses might still allow him to fly if he paid for them himself. The interview sharpened Colville's growing dissatisfaction with life at 10 Downing Street, and he admitted in his diary that he felt bored, unsettled, and desperate for a more active role, increasingly seeing the RAF as his way out.