It is Christmas on the Island of Sodor. Thomas, Toby, and Rheneas are shunting in the Blue Mountain Quarry. Thomas says he is going to pick up a Christmas tree that the logging locos have brought from Misty Island. Rheneas says they do not have a tree and Toby comments that it would not be Christmas without one. Rheneas wants to go to Misty Island to find a tree for his friends, but Thomas is too busy and Toby says that Misty Island is strange and scary. Thomas says this is nonsense, so Toby agrees to take Rheneas.
When they arrive at the Search and Rescue Centre, Toby and Rheneas meet the logging locos, who tell them that there will be plenty of trees on Misty Island. When Toby and Rheneas reach there, Toby says he wants to chuff slowly and carefully, but Rheneas tells him to go fast. Toby chuffs quickly to the Hollow Tree Tunnel. He does not want to chuff forward, but Rheneas tells him to chuff faster and faster. Toby decides that if he closes his eyes, it would not be as scary. He goes fast and they pass some Christmas trees. Rheneas tells Toby to stop, but Toby does not want to; he is too scared.
Toby and Rheneas come up to the Shake Shake Bridge. Toby is scared and does not want to cross, so he closes his eyes and races over the Shake Shake Bridge. They race around Misty Island and pass more Christmas trees. Rheneas tells Toby to stop, but he does not; he is too scared. Then the mist comes down. Toby stops because he is scared. Rheneas tells Toby to go fast, but Toby can't as he is too frightened. Rheneas is worried that his friends will wake up and still not have a tree. Toby explains that he finds going fast scary and would prefer to go slowly. Rheneas agrees and, with the help of the logging locos, the engines go slowly and carefully and find a perfect tree. Toby realises that when he is not going fast, Misty Island is not scary after all and he keeps his eyes open the entire time.
Rheneas and Toby return to the Blue Mountain Quarry. The engines there are all amazed and agree it is a wonderful Christmas surprise.