Cora swam back to Mo.
"I know you're scared.
But we have to find Sally's eggs."
Mo took a deep breath.
"Okay, I can do it. Let's go."
They followed the arrow to Riptide Cave.
The cave was dark and creepy.
"I don't like this place," Sally said.
"Me neither," Mo said.
"What if we get trapped?"
"Don't be silly," Cora said. "Follow me."
Rumble! Rumble!
A strong wave pushed them in.
"Hold on to me!" Cora yelled.
She used her suckers to grab a rock.
Water rushed past everyone.
Then it slowed down.
"Whew!" Mo said.
Suddenly Sally pointed up high. "I see it!
My egg case!"
The egg case was caught on a rock.
Sally tried to reach up with her tail.
"Ugh! I'll never reach up there!"
"I'll try something." Mo puffed himself up big.
He squirted water at the case.
But that didn't help.
"Let me try." Cora reached up with an arm.
But another wave rushed into the cave.
Everyone was swept deeper inside!