The Search Guard Successor (S.G.S.) Foundation (サージェス財団 Sājesu Zaidan?) is a fictional organization in the Japanese Super Sentai series GoGo Sentai Boukenger that collects hidden treasures that have suddenly begun to disappear all over the world. These treasures include relics from early civilizations, sunken ships, unexplored regions, and fossils of animals long gone, all of which are called "Precious". The S.G.S. discovered these Precious and organized a secret team to defend them from those who wish to use the relics' powers.
Chief Satoru Akashi/Fiery Adventurer Bouken Red (明石 暁/熱き冒険者ボウケンレッド Akashi Satoru/Atsuki Bōkensha Bōken Reddo?) was once an enthusiastic treasure-hunter known as the "Immortal Fang" (不滅の牙 Fumetsu no Kiba), the tragic deaths of his partners Kyoko and Masaki in a blaze trap made him retire, only to be hired by SGS. With a calm exterior, Satoru actually hides hot blood inside, as evidenced when he simply catapulted Masumi and Natsuki into the GoGo Dump's bucket and carried them and an entire tub of dirt and gravel at full throttle out of the Goodomu temple before dumping the entire load upon coming to a full stop. He says "Attack!" and simultaneously snaps his finger at the end of each order he gives to the others. He refers to the other Boukengers by their respective colors, something that Masumi has a thing against. He is also seemingly oblivious to Sakura's heavily implied attraction to him. He became filled with self-doubt in Task 4 after GoGo Vehicles 1~5 were buried under ice in a deep crevasse, the resulting suffering of his teammates sparked his memories of Kyoko and Masaki. It took his mighty willpower for him to control the overload-prone GoGo Drill and prevent history from repeating itself. Satoru used to be a huge fan of Jimon Kagawa's writings about heroes. He is a constant rival of Ryuoon and took Ragi, a human whom Ryuoon had transformed into a Wicked Dragon, under his protection and received "the Greatest Adventure" while restoring the Water Metropolis. Satoru was given the offer to quit the Boukengers and join SGS Rescue, but he refused, because he likes to have his own adventures. Instead, he gave Eiji the GoGo Changer. During the events of the Boukenger movie, Satoru encountered his father Kouichi, whom he eventually settled his affairs with.