Murdoch is Sodor's largest and strongest goods engine.
Murdoch was designed by Robert Riddles and built at Swindon Works in 1960. He was brought to relieve the engines of their heavy workloads in 1967 after his with drawl. He was big and strong, so the other engines were eager to learn more about him. Murdoch, however, disliked the noise of their chatter and got cross at Salty and Harvey when they inquired about his past exploits. The next day, Murdoch finally had a chance to pull a train in the quiet countryside, but his journey was interrupted by a flock of stray sheep. Murdoch had to wait with the noisy sheep until Toby could bring the farmer to lead them away. That night, Murdoch found Salty's and Harvey's company a relief.
Murdoch was happy, but shy about being decorated during the May Day festivities.
On one windy autumn day, a large red carpet landed on the back of Murdoch's goods train, unbeknownst to Murdoch. Percy briefly chased down after it, until the heavy winds blew it away again.
Emily once needed Murdoch's help when she became stranded in the mud and near the end Emily asked him which track should she take; Murdoch told Emily that the tracks on Gordon's Hill were being cleared and told her to take the valley route instead.
In spite of his size, Murdoch is gentle and shy. He prefers peace and quiet, also he can work very hard with any job he has, and his favourite hobby is to have a quiet run through the countryside.
Murdoch is based on a BR standard class 9F goods engine, approx. 66 ft 2 in long, the last make of steam engines to be built for British Railways before "Tornado." He is the North Western Railway's youngest steam engine and relies on the knowledge of Henry, Gordon, and James to get things done. He is friends with Henry, Gordon, James, Bear, and Toby. He is enemies with Diesel, The Diesel, D199, Old Stuck Up, and Diesel 10.
Murdoch is painted orange with green and red lining. He has smoke deflectors, on which he wears red nameplates with gold lettering. He also wears a memorial plaque in his cab, which reads "In Memory of David Mitton 1939-2008."
- こうぞう しおや (Japan; 第7シーズン)
- りょういち ふくざわ (Japan; 第12シーズン)
- Gabriel Rama (Mexico)
- In the UK, Murdoch has a Scottish accent in the 12th series.
- Murdoch has a low whistle.
- Murdoch's BR number, 92251, is actually fictional: the highest number for the 9Fs was 92250.