Minamoto no Sanetomo and Minamoto no Ichiman, Yoriie's son, and very close to the Hōjō, who was planning to become the next shōgun. Yoshikazu began to suspect something based on the attitude of Tokimasa, Masako, Ichiman, and Sanetomo, and hatched a plot to capture and assassinate Tokimasa. With the help of Ōe no Hiromoto, a trusted ally, Tokimasa found out about the plan and invited Yoshikazu to his home in Kamakura for Buddhist services. After Hiki exited the services, bakufu troops executed him. Following that, Hōjō troops entered Hiki's residence and executed high-ranking members of the Hiki clan, including Minamoto no Ichiman, who, though close to Tokimasa, was also close to his maternal grandfather. Shōgun Yoriie, bedridden, abdicated. He went to Shuzenji in Izu but was murdered in 1204. It is thought that this was plotted by Tokimasa. Minamoto no Sanetomo After the death of Yoriie and Ichiman, Tokimasa installed Yoritomo's second son, Minamoto no Sanetomo, as the next shōgun. Tokimasa began to chair the Mandokoro, while he and Ōe no Hiromoto exercised absolute power. In 1204, after the assassination of Yoriie, Hōjō Masako lost trust in her father, as she believed that he was behind the assassination of her son. Soon afterwards, Tokimasa was convinced by one of his allies, Hiraga Tomomasa, that Hatakeyama Shigetada, who was married to Tokimasa's youngest daughter, was inciting rebellion in Kyoto against the Hōjō. Tokimasa, angered, ordered his two sons, Hōjō Yoshitoki, his heir, and his other son, Hōjō Tokifusa, to execute Hatakeyama. Yoshitoki and Tokifusa, who enjoyed good relations with their brother-in-law, protested, but Tokimasa ordered the execution of Hatakeyama himself. From then on, Yoshitoki, Tokifusa, and their younger sister lost trust in their father and his meddling. It is believed Hatakeyama was a rival power-holder to Tokimasa. Later life In 1205, Yoshitoki heard rumors from samurai that Tokimasa was planning to have Shogun Sanetomo assassinated. He heard that the heir was none other than Hiraga, who was responsible for the death of Hatakeyama. Yoshitoki, furious, and Masako, who was also scared about the fate of her last son, put Sanetomo under protective guard and had Hiraga executed in Kamakura in 1205. Yoshitoki then threatened to rebel against his father. Tokimasa realized that Shogun Sanetomo was under protection, and he had no more allies left. He thus shaved his head, became a Buddhist monk, and retired from his post of shikken and