When the family learn that Leslie has three girlfriends, Louisa decides to help him choose which one to pick.
Louisa and Larry are both devastated to find that a dear relative has died.
Larry travels with Louisa to Aunt Hermione's Bournemouth home.
The family receives a telegram from Larry, who is in Athens for a short trip, announcing that he has a friend coming to stay – Prince Jeejeebuoy. Concerned about Gerry's education, Louisa also seeks advice from Theo.
Spiros spends time with a glamorous Italian family who have recently arrived on the island. Louisa is jealous of the attention he is paying their new neighbors and invites the new neighbors over to learn more about them. She ends up convinced they are hiding something, while Margo feels threatened by their eldest daughter. Larry joins the fire service, and Gerry falls in love.
The family plan a party to celebrate Gerry’s 13th birthday, but when a plague of mosquitoes descends, they are forced to hold it inside. As the party planning progresses, Louisa is finding it hard to accept that her youngest is growing up. Gerry insists that he doesn’t want a fuss, but gets frustrated and upset when the party is clearly aimed at someone much younger. Trying to pick up the mood, Margo’s transformation of an otherwise disastrous party results in hilarious antics as everyone but Spiros seems to join the party spirit. His distant behaviour concerns Louisa who wonders why he has locked himself in a room to sing sad love songs.
Louisa finds it more than a little awkward when Larry invites Henry Miller to stay. Insisting on walking around naked, the liberal contents of Henry's novels raise heated discussions within the family.
Meanwhile, with the Greek government clamping down on ‘immoral behaviour', Sven is arrested due to his sexuality. Larry is incensed and demands Margo obtain books on miscarriages of justice and fighting fascism from the Countess. However, learning that she is not permitting anyone to enter her villa, Larry takes matters into his own hands.
In the Series 3 finale, the family meets members of a travelling circus, and gets involved in helping them to drum up business. Larry falls in love with a contortionist, while Margo takes to the ring in person to perform a very dangerous act. Gerry is more concerned with making sure all of the animals featured in the show are well-treated. Spiros cannot bring himself to return to his empty house and begins spending more and more time at the Durrells' home - but the magic of the circus brings him and Louisa closer together.