without a home, splinter is forced to run away and live in new york city's sewers. due to a traffic accident, four baby turtles and a canister of mutagenic ooze are sent down into the sewer. the canister mutates both splinter and the turtles. splinter names the four turtles leonardo, donatello, raphael, and michelangelo (after a book on renaissance artists that he found in a storm drain) and trains them in the arts of ninjutsu so that they can avenge his dead master while raising them as his own sons.