Question: Michael Crichton and Stephen Gurewitz, have which mutual occupation?
Context: The Andromeda Strain is a 1969 techno-thriller novel by Michael Crichton documenting the efforts of a team of scientists investigating the outbreak of a deadly extraterrestrial microorganism in Arizona.  "The Andromeda Strain" appeared in the "New York Times" Best Seller list, establishing Michael Crichton as a genre writer. Travels (published in 1988) is a nonfiction book by Michael Crichton that details Crichton's attempts to leave his medical education at Harvard Medical School, followed by his subsequent travel to Los Angeles and adventures continuing his professional writing career, beginning with "The Great Train Robbery" (1975).  After his initial book became a movie starring Sean Connery, Crichton describes his adventures over the world, and ultimately his experience with mysticism, including out-of-body experiences, astral projection, and fortune-telling. Jurassic Park is a 1990 science fiction novel written by Michael Crichton, divided into seven sections (iterations).  A cautionary tale about genetic engineering, it presents the collapse of an amusement park showcasing genetically recreated dinosaurs to illustrate the mathematical concept of chaos theory and its real world implications.  A sequel titled "The Lost World", also written by Crichton, was published in 1995.  In 1997, both novels were re-published as a single book titled "Michael Crichton's Jurassic World", unrelated to the film of the same name. Grave Descend is a novel written by Michael Crichton under the pseudonym John Lange.  It was originally published in 1970, and later re-released in 2006 as part of the Hard Case Crime series.  For this release, Michael Crichton did an overall revision of the text.  The novel was nominated for the Edgar Award in 1971.  Hard Case Crime will republish the novel under Crichton's name on October 29, 2013. The Lost World is a techno thriller novel written by Michael Crichton and published in 1995 by Knopf.  A paperback edition (ISBN  ) followed in 1996.  It is a sequel to his earlier novel "Jurassic Park".  In 1997, both novels were re-published as a single book titled "Michael Crichton's Jurassic World", unrelated to the 2015 film of the same name. Binary is a techno-thriller novel written by Michael Crichton in 1972 under the pen-name John Lange.  Crichton also directed "Pursuit", a television film version.  The story of both the book and the film revolve around a deadly nerve agent composed by combining two different chemicals.  Hard Case Crime republished the novel under Crichton's name in 2013. John Michael Crichton ( ; October 23, 1942 – November 4, 2008) was an American best-selling author, screenwriter, film director and producer best known for his work in the science fiction, medical fiction and thriller genres.  His books have sold over 200 million copies worldwide, and many have been adapted into films. Stephen Gurewitz is an American film director, actor, and film editor.  He is best known as part of the 2010s American indie cinema movement with his breakthrough work "Marvin Seth and Stanley" also starring "Girls" co-star Alex Karpovsky.  In his review for "The New York Times", critic Neil Genzlinger concluded "we never do get to know Marvin or Stanley very well."  In his review for "The New Yorker", critic Richard Brody deemed the picture "not to be missed" and said of Gurewitz's performance that it "brings the torment of quiet desperation and the pride of frustration to life with great humanity." Micro is a techno-thriller novel by Michael Crichton, published posthumously in 2011.  Upon his death in 2008, an untitled, unfinished manuscript was found on his computer, which would become "Micro" and complete his two-book deal with publisher HarperCollins.  HarperCollins chose science writer Richard Preston to complete the novel from Crichton's remaining notes and research, and it was finally published in 2011.  "Micro" is Crichton's second posthumous novel; "Pirate Latitudes", a historical thriller, was also found on his computer and published posthumously in 2009. An apparent contradiction in the observed cooling behavior of Antarctica between 1966 and 2000 became part of the public debate in the global warming controversy, particularly between advocacy groups of both sides in the public arena including politicians, as well as the popular media.  In his novel "State of Fear", Michael Crichton asserted that the Antarctic data contradict global warming.  The few scientists who have commented on the supposed controversy state that there is no contradiction, while the author of the paper whose work inspired Crichton's remarks has said that Crichton "misused" his results.  There is no similar controversy within the scientific community, as the small observed changes in Antarctica are consistent with the small changes predicted by climate models, and because the overall trend since comprehensive observations began is now known to be one of warming.  At the South Pole, where some of the strongest cooling trends were observed between the 1950s and 1990s, the mean trend is flat from 1957 through 2013.
Answer: film director