Juro Wakakusa, a 6-dan boy known as Judo-kun, wins the World Judo Championships. On his way home from the celebration, he is attacked by mysterious men, but it turns out to be an attempt by a high-ranking Indian official who wants him to come to India as a judo teacher. Later, when Juro arrives in India with his younger sister Emi, and are targeted by a secret society that aims to kill Poda, a high-ranking Indian official. Juro and his friends are in danger in a foreign country!?