Blade Runner's dark paranoid atmosphere—and multiple versions of the film—adds fuel to the speculation and debate over this issue. In Do Androids Dream of Electric Sheep?, Rick Deckard (the protagonist) is at one point tricked into following an android, who believes himself to be a police officer, to a fake police station. Deckard then escapes and "retires" some androids there before returning to his own police station. Deckard takes the Voight-Kampff test and it fails to indicate that he is an android.
Harrison Ford, who played Deckard in the film, has said that he did not think Deckard was a replicant, and also states he and the director had discussions that ended in the agreement that the character was human. According to several interviews with director Ridley Scott, Deckard is a replicant. He collects photographs which are seen on his piano, yet has no obvious family beyond a reference to his ex-wife (who called him cold fish). In a scene where Deckard talks with Rachael, their eyes both appear to shine, suggestive of replicants.[original research?]
In the Director's Cut, police officer Gaff (played by Edward James Olmos) leaves Deckard an origami Unicorn a day after Deckard dreamed of one. Just before Deckard finds the unicorn, Gaff says to him in passing, "It's too bad she [Rachael] won't live...then again, who does?". A unicorn can also be seen briefly in a scene in J. F. Sebastian's home, amongst scattered toys (to the right of a sleeping Sebastian, while Pris snoops around his equipment). A unicorn also appears in a dream of Deckard's in the Director's Cut and as explained in the film, Rachael's memories are known by her creators, such as the memory Rachael has of spiders hatching. That Gaff is leaving an origami unicorn at Deckard's house may imply that Gaff knows about Deckard's unicorn dream.
Author Will Brooker has written that the dream may not be unique to Deckard and that unicorn dreams may be a "personal touch" added to some or all of the Nexus 6 replicants' "brains." Since we are not privy to the dreams of the other replicants, this is unknown. From this one could also speculate that Gaff is a replicant and may share the same embedded memory.
Paul Sammon, author of Future Noir: The Making of Blade Runner, has suggested in interviews that Deckard may be a Nexus 7, a new replicant type who possesses no superhuman strength or intelligence but neurological features that complete the human illusion. Ridley Scott has mentioned "Nexus 7" and "Nexus 8" replicants as possibilities in a sequel to the film. Sammon also suggests that Nexus 7 replicants may not have a preset lifespan (i.e., they could be immortal).
Sammon wrote that Ridley Scott thought it would be more provocative to imply that Deckard was a replicant. This ties back into the theme of "what is it to be human?" What is important is not whether Deckard is a replicant but that the ambiguity blurs the line between humans and replicants.
When Scott was asked about the possibility of a Blade Runner sequel in October 2012, he said, "It's not a rumor — it's happening. With Harrison Ford? I don't know yet. Is he too old? Well, he was a Nexus 6, so we don't know how long he can live. And that's all I'm going to say at this stage."