Jacobs conducted hundreds of hypnotic regression sessions with abductees, identifying common patterns and narratives. He argued that abductions represent a systematic program by extraterrestrials.

Jacobs earned a PhD in history from the University of Wisconsin‑Madison and taught history at Temple University until his retirement.

Notable works: Secret Life, The Threat, Walking Among Us

Representative statement: Jacobs has asserted that alien abductions are real and that the beings involved have a long‑term agenda involving human‑alien hybrids.

Jacobs's work is controversial due to the use of hypnosis, which critics argue can create false memories. Supporters credit him with meticulous documentation of abduction accounts.

Jacobs is a central figure in abduction research, though his conclusions have sparked debate even within the UFO community.