Rocky is a large breakdown crane, who is part of the Sodor Search and Rescue Team.
When Rocky first arrived on Sodor, he was ruled out as "strange" and "awkward" because of his peculiar looks and system. He was ostracised for his lack of engine and need for another engine to move him to other places along the line. In particular, Edward, who is usually kind and considerate, took Gordon too seriously when they were making fun of Rocky unfairly by calling him "new-fangled nonsense". However, when some pipes fell on the track and Gordon crashed into them, Edward soon found out how useful Rocky truly was, and they have been firm friends since.
Rocky likes to lift heavy objects such as engines, coaches and trucks. He is a friendly and careful crane and helps the engines when there is an accident. He takes pride in his work and is always happy to help.
Rocky is painted brick red with yellow hazard stripes on his sides and back.
- Season 1 - Splatter and Dodge (does not speak), Harvey's Goods Train (does not speak), Big Strong Murdoch, Bill and Ben (cameo), and Scruff the Scrapper (cameo)
- Season 2 - Disappearing Diesel, Fire at Ffarquhar, Breakdown Butch (cameo), Back to Misty Island (cameo), Sodor Day (cameo), Pedro Deep Down, A Treasury Christmas (cameo), and Ministry
- Rocky has a much taller cab than his basis, in order to accommodate a face.
- Rocky does not have windows on the front of his cab, making it difficult for the operator to see what is happening.
- Rocky has no visible whistle, despite it being heard once.