Oliver is a wise old excavator who works with Miss Jenny and the rest of the construction machines.
Once, Oliver was excavating a digging site when he discovered the remnants of a dinosaur, which turned out to be a full dinosaur skeleton! Using his precision and expertise he uncovered the vestige of prehistory and showed his discovery to all of Sodor when he was featured in the newspaper the next day!
Oliver and Buster were in the valley at The Little Western Extenstion when they warned Arthur about slippery tracks up the line. Despite heeding their warnings, Arthur triggers an avalanche, to which Oliver assists in digging him out.
Oliver assisted in the restoration of Great Waterton as well as the construction of the Harwick Branch Line, in which he met Marion who had mistaken him for Oliver The Western Engine who had supposedly made a wish so he could be a digger, and the Little Western Extenstion Project.
Oliver unwittingly retrieves Proteus' lamp when digging near Poll-ny-Chrink. Despite believing it to be an ordinary headlamp, he plans to keep it, feeling the lamp has something strange about it. The lamp eventually begins to affect Oliver, to a point in which the lamp sends him into a strange trance. Despite being shaken up, Oliver hides the experience from his concerned friends.
Oliver is precise and cautious, always taking his time. Though the other vehicles occasionally find this annoying as it takes him extra long to do his jobs, his careful attitude has saved the day a number of times. He is wise and friendly and the other Pack members often come to him if they need some advice.
- Season 1: Snow Blind (remastered version only), Scruff's Scaffolding (cameo)
- Season 3: Culdee Fell, Chivalry is Dead
- Web Clips: Timothy, Bill, Ben, and Marion - Meet the Characters! (cameo)
- Oliver's Trackmaster model is used in Enterprising Engines! as an alternative to the lower quality Wooden Railway version.