Peter Cook's wife, Wendy was nine months pregnant when filming began. Director Bryan Forbes promised them that he would let Peter leave the set as soon as Wendy went into labor. He kept his word and Peter made it to the hospital just in time for the birth of his daughter, Daisy. Forbes, Dudley Moore, Michael Caine and Peter Sellers filled his dressing room with flowers and champagne in celebration of Daisy's birth when he returned to work.
When Ralph Richardson was offered the part of Joseph Finsbury, he was finishing work on Doctor Zhivago (1965). Richardson wrote to director Bryan Forbes from the location in Spain and asked if he could wear the same jacket he had worn as Alexander in "Zhivago". Forbes agreed, and Richardson did so.