Gravesworld is the remote planet where the scientist Ira Graves lived and worked with his assistant Kareen Brianon.
Gravesworld is the isolated planet that was home to the scientist Ira Graves, who lived there with his assistant Kareen Brianon. In The Schizoid Man the Enterprise answered a call for medical help from the planet, and an away team that included Data and Dr. Selar beamed down.
They found Graves dying of an incurable disease. Before his death on the planet, he secretly moved his mind into Data's body, and the away team returned to the ship with Kareen and Graves's body. The consequences played out aboard the Enterprise.