"There was a big train crash," Roxy thought.
"I have to help!"
Roxy ran back to her friends.
"I'll be right back, guys.
I want to go see the, um, crocodiles one more time!"
"Wait!" called Jack as Roxy ran off.
"We'll come too. I love crocodiles!"
But Roxy was already gone.
Mara pointed at the sky.
"Look! It's Rocket Girl!"
Roxy flew over the train tracks until she reached the scene of the crash.
It was a huge mess.
Cars from the two trains were jumbled together.
Strange smoke poured from some cars and filled the air.
Zoo animals were running in every direction.
Police officers and a zookeeper were trying to catch them.
Rocket Girl landed next to Detective Smith.
"Is there trouble with your train set, Detective?" she asked.
"Ha-ha." Detective Smith pretended to laugh.
"This is no time for jokes, Rocket Girl."
"I know," said Roxy.
"Was anybody hurt?"
Detective Smith shook his head.
"Luckily no people or animals were hurt.
But now the animals are escaping."
He coughed. "And this smoke is terrible.
The firefighters can't get rid of it."
Roxy looked around.
Two firefighters were spraying the train cars with a hose.
But the smoke was still thick.
Roxy took a deep breath.
Then she blew as hard as she could. Whoosh!
Her super breath blew away the smoke.
"Thank you, Rocket Girl," said the zookeeper.
"Now we can see the animals and catch them!"
As the zookeeper and police officers chased animals, Roxy picked up train cars.
She put them back on the tracks, one by one.
Detective Smith came over with a toucan.
"I think we caught all the animals," he said.
"Let's count them to make sure," said the zookeeper.
The zookeeper counted the animals.
He made notes on a clipboard.
When he was done, he scratched his head.
"One animal is still missing."
Then he gasped.
"Where's Blue Baboon?"
Suddenly a loud sound shook the ground.
"Wah-hu! Wah-hu!"
The zookeeper frowned.
"That sounds like Blue Baboon," he said.
"But louder."
Roxy nodded. "And bigger!"
Stomp, stomp, stomp!
The ground shook again.
Everyone turned to look toward the sound.
A huge cloud of chemical smoke moved across a farm field.
Stomp, stomp, stomp!
"There's something inside that chemical cloud," said Detective Smith.
"Do you think it's . . . ?"
The zookeeper dropped his clipboard.
"Blue Baboon!"