Two Shells and a Tail
When Leo accidentally gets mutated and now has a fish tail, his brothers have no choice but to put him in the ocean. Raph was torn apart over this, it already hurt that he couldn't tell Leo his feelings for him, but now he would barely get to see him.
When Leo was out swimming one day, he was seen by some fishermen. Now, determined to find him again, the city gathers all the fishers to go out into the ocean and capture Leo.
His brothers are very worried, and they don't know what to do. They need to find a safe place for their brother before Leo is captured.