As France neared collapse and the fighting around Dunkirk intensified, John Colville was preoccupied by a private crisis: his unresolved love for Gay Margesson. Although Gay had rejected his marriage proposal two years earlier, Colville remained devoted to her. When he called to confirm a weekend visit to Oxford, Gay was evasive and reluctant, which hurt Colville and deepened his sense that she was careless with his feelings.

Colville nonetheless drove to Oxford on Saturday, May 25. After lunch in a pub, he and Gay went to Clifton Hampden on the Thames, where they lay in the grass and talked. Gay was depressed by the war and the destruction she expected, but Colville still experienced the outing as "sufficient bliss" simply because he was with her.

On Sunday they walked in the grounds of Magdalen College, but their conversation was flat and the day became emotionally disappointing. In Gay's room, nothing changed between them; Gay studied French while Colville slept. They also argued about politics after Gay declared herself a socialist, showing another point of division between them.

Later, the mood improved when they walked along the Isis to the Trout Inn. In beautiful evening weather, they dined beside the river and then strolled along the towpath, and Colville felt profound serenity. Gay seemed briefly to share that feeling, saying happiness could only be found by living in the moment.

That hope quickly ended when they returned to her room and Gay again told Colville that they would never marry. Colville answered that he would wait in case she changed her mind, revealing both the depth of his attachment and his refusal to let go. He spent the night on a sofa in a nearby cottage, with his personal longing unresolved.

While Colville's romantic drama unfolded, the war reached a decisive turn. On the evening of May 26 in London, Winston Churchill ordered Operation Dynamo, beginning the evacuation of the British Expeditionary Force from Dunkirk. In Berlin, Adolf Hitler told his armored forces to resume their advance, though they moved cautiously while Hermann Goring still assumed the Luftwaffe could destroy the trapped British troops, dismissing the evacuation effort as negligible.