Casey Jones becomes an unwanted house-guest in the Turtles' lair, so Raphael takes him topside to get some much needed air. During a routine skirmish with a street gang known as the Purple Dragons, Raph and Casey encounter the Foot Tech Ninja, whose cyber-armor enhances their strength and speed while giving them invisibility. Raphael is kidnapped and then interrogated by Hun, while Casey escapes to get help.