Doctor Elias Giger was a Human research scientist who worked in the later 24th century. Giger was a student of the work of Doctor Bathkin, who had proposed several unusual and controversial theories about achieving immortality. Although no practical diagnosis was made, Giger seemed to be a classic "mad scientist," suffering from acute obsession and paranoia.
Following Dr. Bathkin's untimely death in a shuttlecraft – an incident which Giger blamed on the "soulless minions of orthodoxy" – Giger began pursuing Bathkin's work. By 2373, he had nearly completed work on his cellular regeneration and entertainment chamber, a device that would effectively grant immortality by reenergizing the cells of a person's body. According to Giger, the secret to immortality lay in keeping the cells "entertained".
While at Deep Space 9 in late 2373, Giger purchased a selection of antique objects that included a 23rd century ion-transtator, which he used for his entertainment chamber. Among the other objects in the lot was a 20th century baseball card, which he traded to Jake Sisko and Nog in exchange for a selection of special equipment and materials.