On her first day at work, Sylvia is befriended by Chris Cross, a fellow operator whose mind is more on play than pay.
Sylvia experiences both her first pay packet and her first Saturday shift - when rules are more relaxed under just one supervisor. A chance call from the local barracks leads to a disastrous blind date.
Ronni is fed up with the old-fashioned music that switchboard supervisor Miss Armitage makes them sing in the GPO choir. She decides to set up an alternative-the Teletones, a group modelled on the Beverley Sisters. Dick gets the girls a booking but the date clashes with the choir concert.
Sylvia discovers that the engineers have wired up the girls' private line to a loud speaker and are listening in to all their intimate calls, including details of Pam's affair with her driving instructor Cyril.
An emergency meeting is called when the supervisors discover that the girls have been listening in to the secret Baslow line used by royalty and top ministers.
A boxed cake is brought to the exchange by Miss Marriott and left in the supervisors' room. The girls try to find out who the cake is for, but disaster follows.
Sylvia has to forget her personal problems when a suicidal caller comes through and she has to keep her talking while an attempt is made to trace the number.
Derby's exchange is requested to put forward a competitor for the GPO Personality of the Year and Chris and Sylvia are both nominated as candidates for the regional competition. Chris seems to have most at stake - she is determined to prove to the exchange that she is more than just a pretty face.