The Fat Controller arrives at Tidmouth Sheds to give Thomas a special job. Thomas is to collect the Great Composer from Knapford and take him on a tour of the Island so that he can hear the sounds of Sodor. Thomas is pleased and steams off straight away. On the way to Knapford, Thomas stops to ponder what exactly are "the sounds of Sodor." As he is wondering, he hears birds, animals, and the sea. He decides that these peaceful sounds must be the sounds that the Fat Controller was talking about. Then Percy and Emily clatter down the line, pulling troublesome trucks. As they rattle past, Thomas notices that he cannot hear the peaceful sounds any more. Thomas worries that the Great Composer will not be able to hear the sounds of Sodor with his noisy engine friends clattering along the lines. He decides he will take the composer to places where there are no other engines.
Thomas soon arrives at Knapford where he introduces himself to the Great Composer, who says that he will write his tune as they puff along. First, Thomas takes the Great Composer into the Whistling Woods to hear the woodland waterfall. Then Gordon thunders up with the express. Thomas is annoyed as Gordon has ruined the peace, unaware the Great Composer liked it and is beginning to write out his song. He then races off to the Whispering Woods. The Great Composer listens to the rustling leaves and birdsong. Then Mavis clatters up pulling flatbeds of logs. The Great Composer is pleased, but Thomas is not; he thinks Mavis has disturbed the sounds of Sodor. Mavis explains that she is hauling logs because the quarry is closed, but Thomas is not interested and puffs off, not knowing the Great Composer liked it as well.
As Thomas rolls along, he wonders where he can take the Great Composer. Then he remembers that Mavis said the quarry is closed and decides to head there. At the quarry, James is sitting in a siding and watches Thomas enter. The Great Composer is confused, there are no sounds at all; the quarry is silent. James rolls up to Thomas, but Thomas ignores him and puffs away. James follows and Thomas explains that they must be quiet so that the composer can hear the sounds of Sodor. Thomas is too busy talking to James to notice a barrier ahead on the tracks. Thomas screeches to a sudden stop just in time, and the Great Composer's tune flies out of Annie's window and blows away. Thomas feels terrible, but is a little puzzled as to how the composer managed to write a tune despite the noise. The Great Composer tells Thomas that his engine friends sounded wonderful and Thomas realises that his friends are the sounds of Sodor. The composer is still worried; the concert starts soon, but he has no tune. Thomas has an idea and asks for James' help. Next Thomas and James race to the Whispering Woods where they get Mavis' help. The three engines race to Knapford where they enlist the help of Gordon, Percy, and Emily before heading to the Town Square.
At the Town Square, the Fat Controller is becoming concerned. The Great Composer assures Sir Topham Hatt that the special concert will be worth the wait. Thomas announces the concert which features the sounds of Sodor. The Great Composer conducts as Thomas, Percy, Gordon, Emily, James and Mavis roll back and forth blowing their whistles and honking their horns and bumping trucks. Accompanied by the Sodor Brass Band, the concert is a big success. Afterwards, the Great Composer says that he could not have done it without Thomas' help. Thomas in turn, says that he could not have done it, if it were not for his noisy friends.
Tropes featured in this episode:
- An Aesop: You can get inspiration from anywhere, quiet or loud.
- Description Cut: Whenever Thomas stops at a noisy spot, he quips the composer won't be able to compose there. Cue the composer getting inspiration and writing the song.
- It Was with You All Along: Thomas discovers the "sounds of Sodor" were his noisy friends and places all along, he just didn't know it yet.
