Raych Foss is a recurring character in the Apple TV+ series Foundation. Ryach is Hari Seldon's aide and confidante, privy to Hari's plans for the Foundation. He is portrayed by Alfred Enoch, first appearing in the episode "The Emperor's Peace."
As a young child, Raych Foss was raised on Trantor. At the age of six or seven, he was caught by Hari Seldon stealing two Alvarez folios from the rare books section of Streeling University. Raych's mother had died, and his father had been in a accident while working in the heat sinks. The young boy stole to sell items on the black market to pay for medicine to treat a burn on his father's back.
Raych went on to work for Hari Seldon who had developed a new science known as Psychohistory, a methodology that could predict the large scale movements of societies. Raych is the only person that Hari trusted to know about his plan for the Foundation to be intentionally exiled to the planet Terminus. He meets Gaal Dornick when she arrives on Trantor via the Star Bridge, and escorts her to the Imperial Library to meet with Hari. After the meeting, and Gaal learning that she is likely to be arrested in the morning, Raych takes her to the Synnaxian Seer Church before escorting her to the hotel. Raych and Gaal begin to forge a connection as Hari's plan unfolds and the Empire exiles the project to the edges of the galaxy following the terrorist bombing of the Star Bridge.
Raych joins the crew of the Foundation's slow ship en route to Terminus, along with Hari, Gaal, and over seventeen hundred other volunteer colonists. During the journey, Raych and Gaal developed an attraction that blossomed into a relationship. They kept it a secret from Hari on Raych's insistence since he believed that Hari would not approve since relationships were a distraction from the work.