Bears (1976). Lancaster conceived several key scenes in the film, including the Norris-Thing biting Dr. Copper, and the use of blood tests to identify the Thing, which Carpenter cited as the reason he wanted to work on the film. Lancaster said he found some difficulty in translating Who Goes There? to film, as it features very little action. He also made some significant changes to the story, such as reducing the number of characters from 37 to 12. Lancaster said that 37 was excessive and would be difficult for audiences to follow, leaving little screen time for characterization. He also opted to alter the story's structure, choosing to open his in the middle of the action, instead of using a flashback as in the novella. Several characters were modernized for contemporary audiences; MacReady, originally a meteorologist, became a tough loner described in the script as "35. Helicopter pilot. Likes chess. Hates the cold. The pay is good." Lancaster aimed to create an ensemble piece where one person emerged as the hero, instead of having a Doc Savage-type hero from the start. Lancaster wrote thirty to forty pages but struggled with the film's second act, and it took him several months to complete the script. After it was finished, Lancaster and Carpenter spent a weekend in northern California refining the script, each having different takes on how a character should sound, and comparing their ideas for scenes. Lancaster's script opted to keep the creature largely concealed throughout the film, and it was Bottin who convinced Carpenter to make it more visible to have a greater impact on the audience. Lancaster's original ending had both MacReady and Childs turn into the Thing. In the spring, the characters are rescued by helicopter, greeting their saviors with "Hey, which way to a hot meal?". Carpenter thought this ending was too shallow. In total, Lancaster completed four drafts of the screenplay. The novella concludes with the humans clearly victorious, but concerned that birds they see flying toward the mainland may have been infected by the Thing. Carpenter opted to end the film with the survivors slowly freezing to death to save humanity from infection, believing this to be the ultimate heroic act. Lancaster wrote this ending, which eschews a The Twilight Zone-style twist or the destruction of the monster, as he wanted to instead have an ambiguous moment between the pair, of trust and mistrust,