Proteus is a legendary narrow-gauge tank engine with a magic lamp hung upon his funnel.
Proteus was a very old engine from the hills of Sodor with a magical lamp. Legend has it that his lamp was magic and if any engine ever found it, their wishes would come true. The clues to finding the magic lamp are feeling a rush of wind when the lamp is near, hearing a strange creaking sound, and see a flickering light that shines on and off.
In the twelfth season, Miss Marvel, a famous storyteller, read stories about the legend at special show. Later, Peter Sam found a neglected statue of Proteus that was lost for many years. The statue then restored and is now preserved in a park near the Skarloey Railway.
Proteus is painted bright yellow with red lining. All of Proteus' merchandise shows him with a nameplate, even though he never had one in the television series. Proteus' TrackMaster model depicts him with gold side rods instead of his original, silver ones.
- Season 9 - The Magic Lamp (does not speak)
- Season 12 - Mountain Marvel (mentioned, appears as statue)
- Proteus uses the same model as Sir Handel, however he has larger cylinders. This is because his model appears to use Peter Sam's chassis, as green edges can be seen underneath Proteus' bufferbeam and cylinder.
- The statue of Proteus is missing his signature lamp.
- Some TrackMaster releases of Proteus shows him carrying the number 3, like Sir Handel. This may have been a factory-error of using Sir Handel's TrackMaster model with a different face and added headlamp.
- He may be named after the sound font family used from Season 1 - 7.