It had been almost a year since Thomas left the Island of Sodor to travel around the world and ever since he came back, so much had happened. A new monkey habitat had opened at the Animal Park, Darcy had joined the Sodor Construction Company, the animals from the Animal Park had taken refuge at Tidmouth Sheds when the boiler in their winter house broke down on Christmas Eve and there had been a big Technology Fair at Ulfstead Castle.

Some new friends had also come to live on the island. One of them was an old tank engine called Sonny. He used to work for two thieves who tried to steal from the Fair, but he soon proved he was Really Useful and now lives happily on Sodor.

One day, Sonny was shunting trucks in Knapford Yard when suddenly, there was a clank and a wheeze as he sputtered to a stop. "Ugh, ouch," he mumbled.

Everyone looked at Sonny with worry. "What's wrong, Sonny?" Thomas asked.

"His main steampipe has gone," said his Driver. "No more work for him today, I'm afraid."

Sonny sighed. "I guess I'm no' the engine I once was, Thomas. My frames just aren' holding up like they used to."

Later, the Fat Controller came to see Sonny at the Steamworks. "When was the last time you had a major repair, Sonny?" he asked.

"Many years ago, Guv, before I went around stealing things." Sonny looked sad.

Kenji was close by, waiting to be repaired. "How did you become a thief, Sonny?" he asked.

"I never really was, bu' I didn' 'ave a choice."

"Well, what were you like before and how did you get here?"

Sonny felt uneasy. "I…I havn' though' about my past for a long time. It's no' a pre'y story."

"We all know those thieves made you do those things," said Kenji, "but the Fat Controller gave you a second chance to be Really Useful again. Everything is better now and I'm sure if everyone knew, they would be able to help you more."

"…All righ'. So, the old engine began, and this is the story he told.

Many years ago, Sonny worked in a Coal Mine on the Mainland. He lived with many other engines, and they were all kept busy shunting trucks all day long. They took it in turns to pull their coal trains to the Main Line where the bigger engines would collect them. Sometimes, they would even take their trains along the Main Line and deliver the coal themselves.

Sonny and his friends loved their work. Shunting came naturally to them, but they felt very important when they got to pull their trains on the Main Line. Eventually, they were asked to help with passenger trains too and this made them very happy. Sometimes, the Main Line engines would help them too.

Then, hard times befell the Mine. Workmen went on strike or lost their jobs, and the engines had less work to do. One day, Sonny was moved to the far side of the Yard. He sat there for days, and he became very worried.

"Cheer up, old friend," the other engines would tell him. "You'll be back at work soon."

But Sonny was doubtful. "I'm no' so sure. Wha' if the Mine doesn' need me anymore? I'll be sold, or even scrapped."

"The Manager would never scrap you. You work as hard as any of us." Sonny was grateful for his friends' kind words, but he was still worried about what would happen to him.

Not long after that, the Mine was closed for a while and the engines waited to get back to work. One wet and misty night, as Sonny slept in the siding, he awoke to the sound of something clattering. "Oo's there?" he mumbled, sleepily.

"Oh, there's no need to worry, little engine," said a voice. "It's time for you to get back to work."

Sonny was surprised. His eyes opened wider as he looked around, but the buildings were dark, and the only other sound was the heavy pattering of the rain. Sonny was confused as he felt warmth spread through his boiler. "Wha's going on?" he finally asked.

"Oh, you'll see."

Finally, Sonny had steam and he felt his wheels begin to move. He stared into the darkness. No one else was around and his lamp wasn't even lit. It was then that he realized what was going on. "HELP! THIEVES!" he shouted.

"Silence, you siding-sitter!" the voice called back.

Luckily, Sonny had been heard. The other engines awoke and saw what was happening. "Sonny?! Where are you going?!" they called.

"Agh! we've been spotted!" shouted another voice.

But Sonny couldn't go any faster. "THIEVES!" he called again as he puffed out of the Yard. With his lamp out, it was hard for him to be seen, and he soon disappeared into the night. He puffed along to the Main Line Junction where another man was waiting for them.

"We've go' 'im, Cecil," said one of the voices in the cab.

"Brilliant, let's go."

After crossing the Junction, Sonny slowed down as Cecil turned the points and climbed aboard. Sonny traveled along the Main Line until he came to an old track he had never been down before. Once more, the points were switched, Sonny clattered over them, and they were changed again before the thieves sent him up the old track.

Trees and bushes grew all around, the sleepers were rotten, and the rails were rusty. It wasn't long before Sonny saw a group of men standing around a fire. He stopped, and the three men climbed down from his cab as the others gathered around.

"Well boys, here it is," said Cecil.

"It's only a tank engine," said one man in the crowd.

"Ah, but this tank engine can do more than just shunt. I've seen him pulling trains on the Main Line; even passengers. Besides, it'll be easier to get around with this than a bigger engine."

Sonny was very scared, but he couldn't bear it any longer. "Wha' d'you wan' with me?"

Cecil turned around. "You are going to help us in our endeavors, little engine," he said. "It's a cruel world out there and, sometimes, you just have to do whatever you can to get by."

"No!" said Sonny crossly, "I won' do it! I work hard to earn my keep!"

Cecil was standing no nonsense. "Now, you listen to me, you rotting kettle of rivets. Either you help us…or we melt you down and sell you for parts." Sonny shivered and looked at his buffers. "That's better." Cecil paused for a moment as he looked at Sonny. "Now, don't be like that. You should be thanking us. You would've been scrapped anyway if my mates hadn't come along. We can ensure your survival. We can keep you working and out of harm's way." Sonny knew he was trapped with no way out, but all he could do was to listen to them, and they wouldn't harm him. Reluctantly, he agreed. They damped down his fire and the next morning, they gave him a new coat of paint to make him harder to recognize.

Years went by and Sonny spent his days sneaking around with the thieves, waiting until the coast was clear and stealing things, usually helping them get away. He soon started to find it exciting to wait until no one was looking and sneaking around, but he still felt bad about what he was doing, and he felt uncomfortable when he came across other engines. Remembering what the thieves had told him, he was careful never to tell anyone anything about them.

"So, there were more thieves besides Baz and Bernie?" Kenji asked.

"Yes," Sonny said quietly. "The police should know abou' the rest o' them by now."

"What happened after that?"

"One day no' long ago," Sonney continued, "the thieves found out abou' the Technology Fair on Sodor. We ventured up to Ulfstead Castle and Baz and Bernie lef' me waitn' while they snuck around.

"Is that when Thomas met you?"

"Yes, and he helped to remember what it is like to be, what he called, a Really Useful Engine. It fel' good to help others again instead of always helping tha' gang o' crooks. Even though they took care o' me, they didn' treat me nicely. When I finally told Baz that I was fed-up, he threatened to scrap me just like Cecil did. It was a threat I had not heard for years.

"I realized I was wrong to find any part of my new job excitn'. I wasn' 'elping anyone but the bad guys and ye', in spi' of all tha', I never forgo' my old friends, my old job or my old Manager, and I of'en though' about 'em when I was alone. I wan'ed to make it up to them, which is why I confessed to Baz, and I think it was what I said that made him wan' to dispose of me.

"I brough' him and Bernie up to the Castle to steal Ruth's plans, bu' only Baz returned. The next thing I knew, I star'ed racing away. Baz had tied my regula'or open, and he jumped out o' my cab as I raced away. I s'pose you know the rest."

Everyone looked at Sonny. They all felt very sorry for him. "Do you miss your old home?" Kevin asked.

"Yes," replied Sonny, "and I miss my ol' friends and my Manager. I wish I could tell 'em I'm all righ'."

Then, the Fat Controller returned. "I've heard everything from the Manager's Office, Sonny," he said, "and I'm sorry you had to go through all of that. Do you remember where the Mine you worked at was?"

Sonny thought. "Merseyside, Guv."

"Then I will contact your Manager at once and let him know you're safe."

Sonny gasped and smiled from buffer to buffer. "You really mean tha'?! Oh, thank you, Guv."

True to his word, the Fat Controller managed to contact Sonny's old Manager explained what had happened. Meanwhile, Victor, Kevin and the workmen spent many days repairing and replacing Sonny's old and worn parts.

At last, Sonny's repairs were complete and after passing his final inspection, the workmen set about giving him a fresh coat of paint. It sparkled in the sun and his brass shone like gold.

"How are you feeling, my friend?" Victor asked.

Sonny smiled. "Much be'er, thank you."

"I'm glad to hear it," said a voice. It was the Fat Controller who had arrived onboard Thomas.

"As am I," said another. Sonny's eyes widened. Annie's door opened and a smartly dressed gentleman climbed down.

Sonny gasped…it his old Manager. "Mr. Colin...Guv!" he cried.

"Hullo, Sonny. It is so good to see you again after all these years."

"I'm very sorry, Gov. I didn't mean to-"

"Sonny," Mr. Colin cut in, "I understand. Sir Topham Hatt explained everything, and I am very happy that you are safe."

"Does this mean I can go back home to the Mines?"

The Manager sighed. "I'm afraid the Mine closed years ago, Sonny."

The old tank engine was worried. "What abou' my ol' friends?"

"Your friends are fine. I visit them quite often these days and they are still working as hard as they ever did."

Sonny was happy for his friends, but then, he had a thought. "So, what's gonna' 'appen to me now, Guv?"

The Manager smiled. "I think Sir Topham Hatt should have the honour of telling you that."

The Fat Controller looked at the old engine. "Like I said before, Sonny, you are more than deserving of a second chance and I am happy to let you stay on my railway."

Sonny grinned. "Thank you, Guv."

"It's what we do here, Sonny. Many engines have found a second chance to be Really Useful here, and Mr. Colin and I feel that you can do the same. You will always have plenty of work to do here and I promise you will be well looked after."

"And I promise to come by and see you whenever I can," said the Manager.

"Hurray for Sonny!" shouted Kevin, and everyone cheered.

Now, Sonny works hard to make sure the North Western Railway runs smoothly. Along with shunting in the Yards, he pulls trucks and passengers too. He finds his work different from working at the Coal Mines, but very happy to be Really Useful again.

Sonny helps out all over the island, but his favorite jobs are at the Ffarquhar Quarry, the China Clay Works and the Blue Mountain Quarry as they remind him of the work he used to do in the old days. The old engine loves his new life and is grateful for his second chance, and Thomas could not be happier for his new friend, Sonny the Mine Engine.