Isaac Mentnor is the senior member of the Backstep team, the eldest of the scientists and often the wisest. His presence is sporadic, often only when he is needed, as he is quite elderly. He is the unofficial "grandfather" of the team.
In his youth, Isaac was involved in many morally questionable tests and experiments, one of which was the development of the insanity virus later unearthed in the town of Dunwych. Though his developments were brilliant, Isaac regretted some of his actions.
He has been married twice. The first time, it was to a woman "with the tinest ankles." After the rapid divorce, Isaac married his beloved wife Claire, who has had at least one child and grandchild. Claire is as steady-minded and kind as her husband, and they clearly love each other a great deal.
Mentnor has been continuously involved in the Backstep program and its background, the Roswell crash of 1947. He has been there since the beginning, and thus was blamed by former chrononaut James Rance for the lack of searching after the older Sphere crashed in the Amazon jungle.
Mentnor offers wisdom and guidance to wayward Frank Parker, and also became friendly (if not friends) with Andrew "Hooter" Owsley. He spends an increasing amount of time in low-profile work, as well as tending his zinnias.
