In the 🎥 I like when Nia the tank engine from the African country of Kenya and a new member of the Steam Team on Sodor. She is a real optimist with a great sense of fun. She is also driven by a strong moral compass and takes being fair and kind to others seriously. She is not afraid to speak her mind when she needs to. Nia is both thoughtful and practical and often comes up with very creative ideas. Her kind heart and infectious enthusiasm never fail to win over others in the end.
She first meets Thomas in her homeland of Kenya when he stops in her yard to collect more trucks to take to Dar es Salaam while in pursuit of Ace. Noticing how heavy his train is getting, she offers to help, but Thomas sternly refuses, stating he can handle it himself. However, she later arrives to help him over a steep hill when the trucks nearly cause him to slide back down it. She later encourages the trucks to sing to raise Thomas' mood during the journey, and to help soothe an elephant that tries to charge Thomas when it was blocking the tracks. When they reach Dar es Salaam, Nia has a chat with her friend Kwaku, but Thomas interrupts before Nia can reveal that her shed was destroyed and she was looking for a new one. After Thomas thanks her for her help, he prepares to board a ship bound for South America and the city of Rio de Janeiro in Brazil. However, Nia decides to join him, much to his chagrin, having wanted to see the world herself.
Thomas remains unfriendly with Nia throughout their journey, but begins to warm up to her after they rescue a crashed Ace and made it through the Amazon rainforest after some difficulty, continuing their journey through Central America and Mexico before reaching North America and the United States. As they make their way through the Grand Canyon, Ace is able to trick Thomas and Nia into splitting their delivery to San Francisco between them and race to see who is the faster of the two steam engines. Thanks to Ace, who wanted to get to the Bonneville Salt Flats, Nia is separated from Thomas, and as a result, thinking that Thomas was in on Ace's trick, she becomes hurt and cross, and continues on alone to China.
When Thomas catches up to her in the Himalayas, she refuses to listen to his explanations for what happened, still hurt and upset about it, but hearing his heartfelt apology, she realises he never meant to upset her and is truly sorry for it. Before she and Thomas can fully make amends, an avalanche caused by Thomas trying to get Nia's attention sweeps her off the tracks and leaves her dangling precariously over a cliff. Thomas attempts to pull her back to safety, but a rock underneath her is dislodged causing her to go over the edge and nearly pull Thomas with her until Yong Bao arrives just in time to save both of them. After Nia is lifted back onto the rails by the breakdown cranes brought by Yong Bao and The Chinese Diesel, she and Thomas prepare to return to the Island of Sodor, with Yong Bao advising they travel through Asia and Europe to get back to the Island of Sodor via The Mainland.
Together, Nia and Thomas make their way back to Sodor, unaware of a signalman in India seeing Thomas and phoning ahead to let the North Western Railway know he was coming home. When they reach the Vicarstown Bridge, Thomas realises that once he crosses it, he'll be home, but Nia will have to go home to Kenya. However, Nia reveals what she had tried to tell Kwaku back in Dar es Salaam before Thomas interrupted her, that she no longer has a home to go back to. Sympathetic to her plight, Thomas offers Nia the chance to stay and work on the North Western Railway, knowing that Sir Topham Hatt would love to have Nia working on his railway. The two engines cross the bridge, returning to Knapford to find a large group of Thomas' friends, human and engine alike, welcoming him home. After Thomas formally introduces Nia to Mr. Percival and the others, Nia prepares to enjoy her new home on the Island of Sodor
