Keisuke disappeared from Santa Ana, California on June 16, 2008. He was abducted by his non-custodial mother, Reiko Nakata Greenberg-Collins. A photograph and vital statistics for Reiko are posted below this case summary. A federal warrant for unlawful flight to avoid prosecution was issued for her on September 15, 2008.

On June 13, two days before Keisuke last saw his father, the court ordered Reiko to surrender her son's Japanese and American passports. Neither of Keisuke's parents were permitted to take him out of Orange County. On June 16, Reiko took Keisuke and her daughter from a previous marriage and flew to Japan. She was born there and her parents, Ken and Miyuki Nakata, live there. According to Keisuke's father, Randy Collins, Reiko's parents sent her to the United States to be educated when she was 13 years old. She stayed with a host family in San Francisco, California during her adolescence. Randy claims Reiko made false accusations of sexual abuse against the father of her daughter. Randy describes her as a very controlling, possessive mother: he says she slept in Keisuke's bed his entire life, breast-fed him until he was four, and limited his contact with his father.

Japanese law refuses to intervene in international custody battles concerning their own citizens, but Randy continues to hope he can recover his son. Keisuke has dual citizenship in Japan and the United States, but he was born in California. His case remains unsolved.