Paul Manheim was a brilliant scientist whose experiments with time on Vandor IV caused distortions that threatened the galaxy.
Dr. Paul Manheim was a scientist who had been expelled from the Federation Science Institute for unauthorised experiments, and later carried out research into the nature of time on Vandor IV. In We'll Always Have Paris his work went wrong, killing his research team and causing time distortions that affected the Enterprise.
Manheim himself was badly injured and shifting between moments in time when the Enterprise brought him aboard with his wife, Jenice, a former love of Picard. Data entered the laboratory to seal the rift, and Manheim recovered and remained with Jenice. Rod Loomis played him.