Mo and Mandy took off.
But Cora stayed behind the seagrass.
She watched the diver swim closer.
"There's the blue box!" she thought.
The diver was wearing the box around his neck.
He held something in his hand.
Cora gulped.
"The diver has a net!" she thought.
Cora started to zoom away.
But—swoosh!
The diver scooped her into the net!
Mo and Mandy were still swimming away.
Suddenly Mo stopped. "Where's Cora?"
Mandy stopped too. "I don't know."
"We have to go back!" Mo said.
Mo and Mandy swam back to the seagrass.
Mandy gasped. "There's Cora!
She's in the diver's net!"
Mo puffed up. "I'll save you, Cora!"
He rushed at the diver.
But Mo's spikes weren't sharp enough.
The diver had very thick skin!
Mo tried to get away.
But soon he was in the net too.
"Help!" Mo said. "We're trapped!"
"No, we're not!" Cora said.
She tried to bite through the net.
Suddenly—click!
A strange, bright light flashed!