Enjoy the fun at St Clare's with the two o'sullivan twins and more and more mystery and adventures and mischief. Watch out The series follows the heroines Patricia "Pat" and Isabel O'Sullivan from their first year at St. Clare's on. Other characters include Alison O'Sullivan (the twins' cousin), Hilary Wentworth, Kathleen Gregory, Janet Robins, Doris Elward, Vera Johns, Sheila Naylor, Roberta "Bobby" Ellis, Pamela Boardman, "Sour Milk" Prudence Arnold, Carlotta Brown (an ex-circus girl), "Catty" Elsie Fanshawe, Gladys Hillman, Mirabel Unwin, Kitty Flaherty (who brings her pet goat, McGinty, to the school), Pauline Bingham-Jones, sisters Claudine and Antoinette, "the Honourable" Angela Favorleigh, Alma Pudden, Anne-Marie Longden, Felicity Ray (a musical genius), Winifred James (the head girl when Pat and Isabel were in the first form), Tessie (the head girl of the second form), Margery Fenworthy (who got expelled from six schools but made a fresh start at St. Clare's), Lucy Oriell (who became Margery's friend), Erica (the troublemaker), Priscilla Parsons (a sixth former who is expelled) and Joan Terry (who got bullied by Priscilla). for the traps

Secret seven is a secret agency where they solve mysteries.