Sarah is a 7-year-old girl with big eyes and a green hat. She lives with her best friend, a quacky, slightly manic fowl appropriately named Duck. Each episode features the pair setting out on simple but exciting adventures as they explore the world in their own imaginative way.
The series follows the adventures of Sarah, a very kind, polite seven-year-old girl, with big eyes, rosy cheeks and a green hat, and her best friend Duck, a Mallard. The central theme is the relationship between these two characters and the adventures they have together. CBeebies state that the show has two learning themes: 'Friendship and imagination' and 'Problem Solving'.