Stevens was an psychologist aboard the ship that geologist Michael Altman, as well as many other scientists, were kept on during the retrieving and studyof the Black Marker. He was one of Craig Markoff's right hand men, he also was probably the one who helped create the Krax. He tested people before they went down on a dive to either check on the Marker's progress, take different tests, or check the bathyscaphes performance. Everyone who he tested was seen as stable but when they went down went insane under the influence of the Black Marker. He helped Craig Markoff every step of the way when they were excavating the Black Marker from the Chicxulub Crater in the Yucatán peninsula. He, along with Markoff killed Michael Altman after he (Altman) destroyed the lab and sank the Black Marker with it and used Altman's reports and logs on the Marker to create Markers of their own while they used Altman as the face of their new religion, Unitology.
- While he appeared to have no interest in the Marker or Unitology at first, he eventually 'half' converted over and convinced Markoff to release Altman from Krax's "playtime" so he could speak to the religious members and help ease tensions among them as he feared they were planning a riot.