Molly is a shy, yellow tender engine.
- Season 1 - Sidney Helps Out
- Season 2 - Golden Engines and Tender Engines Don't Shunt!
- Season 3 - Thomas and the Twins (cameo), Tender Trouble (cameo), and A Happy Day for Alfie
- Season 4 - Bear and the Fish (does not speak)
- Season 5 - The Early Whirlybird
- Season 6 - The Secret At the Steamworks (does not speak), and New Years Blues
- Season 8 - High Winds (cameo)