- "Of all the bits of foliage I could have been, a tree of all things..."
- ―Peter Sam, All the World's a Stage
Peter Sam (formerly known as "Stuart") is a bouncy green engine on the Skarloey Railway.
When Peter Sam was named "Stuart", he worked on the Mid-Sodor Railway with Duke, Falcon, Fearless Freddie, Smudger, Stanley and the Scrap Engine. When the line closed, he was purchased by the Skarloey Railway, and renamed "Peter Sam." During his stay, he has had a plethora of exciting adventures. He almost left a refreshment lady behind at a station, got into a nasty accident at the slate quarry, damaging his old funnel, and crashed into an icicle into a tunnel, causing the already loosened funnel to fall off (which was eventually replaced with a smart new giesel funnel!)
Later in his career, a line of trucks with leaves and broken branches broke away from him and fell off the Old Iron Bridge and into a ravine! The accident, unfortunately, got Peter Sam into a lot of trouble with The Fat Controller! He also found a new location for the Refreshment Lady's Tea Shop, finding an old coach that could be refurbished into a grand tea shop on wheels. Peter Sam later complained about aching pains coming from his giesel funnel, and he was given his old-shaped funnel back.
Peter Sam has not taken the "Gunpowder Conundrum" very seriously on the Skarloey Line, usually joking around with Sir Handel when it is discussed!
Peter Sam collided into Isobella on the crossing, causing a great deal of damage!
Peter Sam currently works at The Blue Mountain Quarry.
When Sir Robert Norramby was searching for King Orry's sword at the BMQ, he switched some points with out permission in order to retreive his horse, only for Peter Sam, who had become a runaway, to crash into a Murk-Stone Lake . After being fished out, it turned out that the sword had been in the lake this whole time, and had drifted into Peter Sam's cab!
Following a poor performance at auditions Peter Sam is cast as a tree for the Skarloey Railway's production of Hamelt, to which is very unappreciative. His chance to shine comes when Freddie experienced stagefright, when he goes on stage and begins to perform a comedy routine. Despite livening up the crowd, he is shunted off the stage by Rusty at the order of Bertram for breaking the 4th wall.
Peter Sam is a very enthusiastic engine but can get a little too excited at times. "He's cocky, but he's nice" the coaches will say, and he rarely complains. He can be a bit gullible occasionally, and can get upset about things that are not necesarily true. He is very optimistic all the same, and when tragedy befalls him, he never really deserves it.
Sir Handel and Peter Sam care very deeply for Duke, their elderly companion from the Mid-Sodor Railway.
He is also wary of Wendy due to his incident with the slate trucks taking place on an incline, which Wendy is.
Peter Sam has a very comedic side to him, and when the Skarloey Railway's production of Hamlet wasn't going as well as he had thought, he stepped right in with a stand-up comedy act and livened up the crowd. It was later considered by many to be the best part of the show, but Bertram strongly disagrees!
- Season 1: Lift Bridge (cameo), The Old Warrior (cameo), Double Whammy, Cannon Fodder and Greg and Lars (cameo)
- Season 2: Two Hearts Burn Together, Pigeon Hunting (cameo), Serendipity, Scot-free (cameo), Mavis and the Tornado, Rosie (cameo), Young Tucker (cameo), Just Another Wild Goose Chase, Munitions (cameo), Swan Dive (cameo), Luke and Millie's Blue Mountain Adventure, Aura of Menace (cameo), All the World's a Stage, Swashbuckler
- Season 3: The Suggestion Box (cameo), Chivalry is Dead, Percy and Asbestos (cameo)
- Peter Sam's 2013 "Dynamite Delivery" model was used from Blunderbuss onwards. And will be replaced by his 2012 model.