Oliver is the number eleven of the North Western railway, he runs the Little Western line with Duck. After the deaths of Toby and Edward, he and the other engines deemed it unsafe to stay at Tidmoth Sheds, so they moved to the Skarloey Railway.
When Percy was kidnapped and Thomas and Gordon went to rescue him, everyone became concerned when neither of the three engines returned. Duck offered to go find them with Phil, but Henrietta refused to let him, so it was decided that Oliver and Toad would go along with Phil instead.
The three stopped on the Viaduct, near the diesels' hideout, and Phil got off, with the intention to go scope out the situation, much to the displeasure of Oliver and Toad. After blowing up the mine and thus blocking the entrance to the quarry, he quickly ran back to the Viaduct where Oliver and Toad were and started Oliver's fire. On the way back they had a run in with Simon and the Blockade Committee, but fortunately they were able to get away in time and soon returned to the Skarloey Railway.
Years later, Oliver brought back S.C.Ruffey after his overhaul.