A romantic relationship in Istanbul ends badly. Lamb hits the panic button when one of his Slow Horses fails to show up for work.

An unexpected turn of events leads to a wedding being hastily arranged. Shelagh finally goes into labour. The arrival of the pill leads to unforeseen consequences.

As tensions with Philip increase, Elizabeth spends time with her old friend Porchey. Churchill’s portrait is painted for his 80th birthday.

Elizabeth rejects protocol by appointing Philip to coordinate her coronation, but his ideas create conflict. The Duke of Windsor returns to London.

With King George too ill to travel, Elizabeth and Philip embark on a four-continent Commonwealth tour. Party leaders attempt to undermine Churchill.

When dense smog cripples London for days and creates a serious health hazard, Churchill’s inaction leaves him vulnerable to his political enemies.

A young Princess Elizabeth marries Prince Philip. As King George VI’s health worsens, Winston Churchill is elected prime minister for the second time.