Fantastic Voyage - Biological Issues and Accuracy

Biological Issues and Accuracy

In the original movie, the crew (apart from the saboteur) manage to leave Benes's body safely before reverting to normal size, but the Proteus remains inside, as do the remains of the saboteur's body (albeit digested by a white blood cell), and several gallons (full scale) of a carrier solution (presumably saline) used in the injection syringe. Isaac Asimov pointed out that this was a serious logical flaw in the plot, since the submarine (even if reduced to bits of debris) would also revert to normal size, killing Benes in the process. Therefore, in his novelization Asimov had the crew provoke the white cell into following them, so that it drags the submarine to the tear duct, and its wreckage expands outside Benes's body. Asimov solved the problem of the syringe fluid by having the staff inject only a very small amount of miniaturized fluid into Benes, minimizing its effect on him when it expands.

Asimov also dealt with another logical flaw in the original, involving extra oxygen needed by the submarine's crew members. In the film, the submarine enters the lung and crew members pump oxygen into the submarine's stores. However, Asimov knew that the miniaturized crew members would not be able to breathe unminiaturized oxygen molecules. So, in the novel, the oxygen from the lung is processed through a miniaturizing device installed on board the submarine; there is no such device in the original film script.

Further literary license is taken for the final swim up Benes's optic nerve to safety. Raquel Welch's character was miniaturized to approximately .1 microns, or 250,000 times smaller than her normal stature of 5'6". If the crew of the Proteus escaped by following the entire two-inch length of the optic nerve, then Welch faced the equivalent of a 520 mile swim with less than six minutes to finish before growing back to 5'6" (thus killing the patient). Even with some de-miniaturizing along the escape route, the crew were still of microscopic size (less than .1 mm) on reaching the tear-driven surf at Benes's cornea - reducing the 520 mile swim to a still daunting five miles (in under six minutes).