Question: Which film, directed by Roger Christian is based upon the first half of L. Ron Hubbard's 1982 novel of the same name? 
Sentence (from "Margaret Grubb"): Margaret Louise "Polly" Grubb (September 22, 1907 – November 17, 1963) was the first wife of pulp fiction author and Scientology founder L. Ron Hubbard, to whom she was married between 1933 and 1947.
Relevant evidence: No