While not credited as Producer, Arnold Schwarzenegger should have been so.
When owner of the movie rights for Philip K. Dick's TOTAL RECALL, Dino DeLaurentiis (KING KONG , FLASH GORDON, CONAN THE BARBARIAN), went nearly went bankrupt, Arnold convinced Carolco Pictures to buy the script rights. The script was re-written for Schwarzenegger's physical stature, which Arnold felt helped the story contrast even more: A powerful man rendered helpless by having his mind stolen.
Verhoven and Schwarzenegger wanted to work together ever since Arnold was originally cast to play ROBOCOP. Once Mario Kassar of Carolco owned the property, Arnold convinced him to hire Verhoven to direct.
When Paul Verhoven read the TOTAL RECALL script that Arnold sent him, he loved it, but wanted to make changes so that it would be more scientifically accurate.
To get the cities of Mars right, production designer William Sandell went to various universities to find out how future habitats on Mars might look. The popular idea was to build structures into rock walls to protect from solar radiation.
According to editor Frank J. Urioste* (DAMNATION ALLEY, AMITYVILLE 3D, THE HITCHER, ROBOCOP, DEEP BLUE SEA), the producers felt that keeping the external shots of Mars would make the final cut too expensive and wanted to leave them out. Frank pleaded his case to Arnold, who in turn convinced the producers not to remove them.
On ROBOCOP, Paul Verhoeven constantly fought with Special Effects supervisor, Rob Bottin (THE FOG, THE HOWLING, John Carpenter's THE THING, TWILIGHT ZONE: THE MOVIE, SE7EN, DEEP RISING) on achieving a realistic look and feel. After Verhoeven saw how good ROBOCOP turned out, he approached Rob Bottin to do the Martian creature designs for TOTAL RECALL, offering Rob full freedom.
Writer Dan O'Bannon (ALIEN, DEAD AND BURIED, HEAVY METAL, THE RETURN OF THE LIVING DEAD, LIFEFORCE, BLEEDERS) had a serious disagreement with Paul Verhoeven, resulting in the two men falling out. Dan wrote TOTAL RECALL as a dark comedy and Paul wanted more action and violence.
So why did the science go off the rails... or did it?
According to Paul Verhoven on the DVD commentary, he wanted accurate science on everything right up to the moment that Douglas Quaid goes under at the Rekall office. Everything in the first 20 or so minutes represents reality. From the moment Douglas gets the implant, the movie is all in Quaid's head and Paul had tons of references throughout the movie to show this was so. Right up to and including Douglas' visit from his wife Lori (Sharon Stone: DEADLY BLESSING, SCISSORS) and Rekall Dr. Edgemar (Roy Brocksmith: WOLFEN, ARACHNOPHOBIA). Edgemar outlines the entire final act in this scene, and Paul felt he was laying all of his cards on the table for the audience.
Douglas Quaid: All right, let's say you're telling the truth and this is all a dream.
Quaid points a gun at Dr. Edgemar's head -
Douglas Quaid: I could pull this trigger and it won't matter.
Lori: Don't, Doug.
Dr. Edgemar: Oh it wouldn't make the slightest difference to me Doug. But the consequences to you will be devastating, because in your mind I'll be dead, and with no one to guide you out you'll be stuck in permanent psychosis.
Lori: Let Dr. Edgemar help you.
Dr. Edgemar: The walls of reality will come crashing down. One minute, you'll be the savior of the rebel cause, and the next thing you know you'll be Cohaagan's Bosom Buddy. You'll also have fantasies about alien civilizations as you requested. But in the end back on Earth, you'll be lobotomized!
The rest of the movie plays out almost exactly like that.
Verhoeven has gone on record saying the ending was in fact a "dream ending", which is why he ended it with a fade to white instead of a fade to black.
*found in the DVD/BLU-RAY featurette and/or at IMDb.