Each year, three brothers Samuel, Jeffrey and Michael Douglas visits their Japanese grandfather, Mori Shintaro whom the boys affectionately refer to as Grandpa, for the summer. Mori is a highly skilled in the fields of Martial arts and Ninjutsu, and for years he has trained the boys in his techniques. After an organized crime ring proves to be too much for the FBI, it's time for the 3 brother NINJAS! To use their martial arts skills, they team up to battle the crime ring and outwit some very persistent kidnappers!
Victor Wong
as Grandpa Mori Tanaka
Michael Treanor
as Samuel 'Rocky' Douglas Jr.
Max Elliott Slade
as Jeffrey 'Colt' Douglas
Chad Power
as Michael 'Tum Tum' Douglas
Rand Kingsley
as Hugo Snyder
Alan McRae
as Samuel Douglas Sr., FBI
Margarita Franco
as Jessica Douglas
Kate Sargeant
as Emily
Joel Swetow
as Brown
Professor Toru Tanaka
as Rushmore
Race Nelson
as Marcus
D.J. Harder
as Hammer
