Role in the film
The lizard footmen originally appear as a pair of wild lizards that reside in the garden of Ella's home. They peeked from behind some pots as Ella poured a drink for an old lady that was revealed to be her Fairy Godmother. They crawled cross the fountain to the greenhouse where Ella and her fairy godmother went to get a pumpkin for the coach. As the pumpkin grew, one of the lizards crawled up it and clung onto a glass panel until it was flung off.
Shortly after she turns Gus, Jacqueline, Matilda, and Teddy (the four mice Ella befriends in the movie) into white horses, the Fairy Godmother looked for something to turn . She noticed the lizards and uses her magic to turn them into footmen. Although the lizards become human, they still have lizard characteristics, such as the green coloring on their skin and outfits, pointy teeth, long tongues, and an appetite for flies.
Upon arriving at the Palace, Ella admits her fears of not belonging to one of them (Mr. Lizard), saying that she is "only a Girl, not a Princess," to which he reassures her, stating that he's not a Footman, just a Lizard, and she should enjoy the night while it lasts. This helps to alleviate her concerns, allowing her to enjoy the said night with Prince Kit.
After Ella leaves the palace in a rush, the scheming Duke and the Captain of the Guards give chase. During the chase, Mr. Lizard (who at this point got back his tail) uses his tail to flip a switch which closed a cast-iron gate and stopped the Duke from chasing them. As the coach rides through the forest while the magic continues to wear off, the lizards were the 1st to eventually change back to normal and crawled into the coach as it changed back into a pumpkin (with Ella also still inside it). Once the coach completely changes back into a pumpkin and breaks, a lizard landed on a piece of the pumpkin while the other lizard flew on another piece that eventually knocked the coachman hat off of Mr. Goose. Both lizards followed the others back to the house, climbing over the wall back to the garden followed by Mr. Goose.
The lizards are seen again at the end of the film where they are seen scurrying around the palace balcony (along with the four mice and Mr. Goose) when Ella and Kit are married as they address the public on a balcony.