Diamond (Formerly known as Ellen-Jane Potts) is the main character in Diamond.

Diamond wasn't always a star. Born to penniless parents who longed for a strong, healthy son, she was a dainty, delicate daughter - and a bitter disappointment.

Discovering she has an extraordinary gift for acrobatics, Diamond uses her talent to earn a few pennies, but brings shame on her family. Then a mysterious, cruel-eyed stranger spots her performing, and makes a deal with her father. Diamond is sold for five guineas, and is taken to become an acrobat at Tanglefield's Travelling Circus.

The crowds adore Diamond, but life behind the velvet curtains is far from glamorous. Her wicked master forces Diamond to attempt ever more daring and dangerous tricks, until she is terrified to step into the ring. But there are true friends to be found at the circus, too: the gentle Mister Marvel; the kindly Madame Adeline; and the glorious Emerald Star, Tanglefield's brand-new ringmaster, and Diamond's heroine.

No.1 Diamond. Diamond is an 8 year old girl, who has a talent for doing handstands ,acrobatics and is talented enough to work at a circus with her dear friend Hetty ( Emerald star ) by her side.

Emerald Star: Emerald Star has been through a lot of daring adventures since she was born and has now found Mr. Tangfield's travelling circus, where she is now the ringmaster, and great friends with Diamond too!

The silver boys: Marvo, Julip and Tag are the three silver boys in Mr. Tangfield's travelling circus. They work well for stacking each other above one another and with their forward flips and sometimes the springboard.

Mr Marvel and his monkeys: Mr Marvel is an elderly, but very kind man to Diamond and Emerald Star both. His monkeys are what make the circus ravishing, and fun with all of them hip-hoping about.

Beppo the clown: Beppo is the one who wanted Diamond to come to his circus in the first place, found doing handstands in the street and is one of the clowns in Tangfield's Travelling circus.

Elijah the Elephant: Elijah is the circus' Major elephant who takes part in astonishing tricks and is led by Mr Tangfield. 

Madame Adeline: Madame Adeline is a very kind and elderly woman who adores Emerald Star and Diamond on stage. When Madame Adeline and Mr Marvel are no longer allowed to perfome in Mr Tangfield's circus, they hope to have a great future together.