Bicentennial Man is based on the novel The Positronic Man, co-written by Isaac Asimov and Robert Silverberg and based on Asimov's original novella titled The Bicentennial Man. The movie follows the existence of the robot Andrew Martin (Robin Williams), an android of the NDR series. Andrew, as he is referred to in the film, is purchased by the Martins in April 2005 to assist the family and is immediately rejected by the elder child of the family, with whom he clashes.

Spoilers ahead: However, the clashes reveal to the family that Andrew has the capability for emotions, and he becomes particularly devoted to the younger of the children, Amanda Martin (Hallie Kate Eisenberg), whom he refers to as "Little Miss". In his time with the Martins, Andrew learns more and more of his surroundings. After accidentally breaking a glass figurine belonging to "Little Miss", Andrew carves a similar figurine out of wood. The family is astonished to see this sign of original creativity in a robot. When Mr. Martin takes Andrew to NorthAm Robotics to inquire if all the robots were like him, the CEO of the company acts like there is a problem and wishes to scrap Andrew, or as he put it, "fix him". Angered by this Mr. Martin leaves the company and allows Andrew to be taken off his regular household duties, for which he was originally intended, and allowed to pursue his creativity. He begins creating masterpieces of clocks and other wood items. After many years have passed Andrew has collected a large sum of money from his inventions to which Mr. Martin believed it fitting that Andrew should have a legal adviser and bank account. When Andrew is damaged, Mr. Martin takes Andrew back to the NorthAm Robotics company but informs the CEO that if they attempt in any way to alter Andrew's positronic brain that they would be liable for the entire projected revenue Andrew's creativity would generate over his operational lifespan, a nearly infinite amount. Andrew eventually leaves the service of Martins much to the dismay of Mr. Martin.

Over the course of many years Andrew sets out to see if there are any other that are similar to him but in the end he finds none. He does however stumble upon a female NDR, named Galatea, who is owned by Rupert Burns, the son of the man that designed all the NDR series robots. Andrew is attracted to Galatea after seeing that she can dance but soon finds out the only reason she seems unique is because her personality chip is activated. She continues to be a source of great annoyance to Andrew for the rest of the movie because she is overly chipper and reminds him continually that he is mechanical. Rupert has been working with synthetic skin to create a more human looking robot but has no funding. Andrew pledges his support and begins his process of slowly assimilating himself into a human. In his quest to become more human, Andrew analyzes the entire collection of human anatomy and physiology and creates designs for artificial organs and eventually a central nervous system. Andrew, believing himself to have human qualities unknown to any robots, goes to the World Congress and asks them to pass a bill declaring that he is human.

Andrew had retained his connection with Amanda and eventually her granddaughter, Portia (Embeth Davidtz). Before Amanda marries her husband, she implies that she fell in love with Andrew (at a time where Andrew was robotic and unable to feel love and loss, but had twenty or so years of education and growth behind his "uniqueness") and Andrew, after the Little Miss has passed on and as he acquires more human parts, falls in love with Portia and they establish themselves in a marital relationship, though it is unrecognized by law.

The World Congress leader reminds Andrew that he is artificial. Andrew asks, "You yourself, sir, own one of my kidneys, do you not?" The World Congress leader agrees. Andrew states, "Then you are artificial in part." "In part, yes", replies the World Congress leader. "Then I am human in part", replies Andrew. The World Congress leader asks Andrew, "Which part?" Andrew pats the middle of his chest. "This part", he says, telling the World Congress of his ability to love and feel emotions. The World Congress leader reminds Andrew that he still has a positronic brain and in that sense is immortal and that the human race can never, and will never, tolerate an immortal human. Andrew simply replies quietly, "One is glad to be of service", and leaves with Portia.

Over the course of the next 100 years, he proceeds to turn himself biologically human and thus allowing him to age. Andrew again attends the World Congress now appearing old and frail. The Speaker of the said Congress agrees to at least debate the issue and asks him why he wants this. To his reply he states, "To be acknowledged for who and what I am; no more, no less. Not for acclaim, not for approval but the simple truth of that recognition has been the elemental drive of my existence and it must be achieved if I am to live or die with dignity." At the end of the film, Andrew Martin is lying on his death bed with Portia, being attended to by a perky nurse. A broadcast begins on a television/holographic screen. The Speaker of the World Congress appears and begins to announce the court's decision. Before she finishes, Andrew dies. The Speaker goes on to say that it is declared, that Andrew Martin is recognized as the oldest, non-biblical, human being in history, aged 200 years old. The Speaker also finally validates the marriage between Portia and Andrew. The film ends with Portia instructing the nurse to switch off her life support machine ("Unplug me", further blurring the distinction between man and machine), with the additional comment of, "That's an order," implying that the nurse is a person that must take all orders, i.e. an android. Portia's further comments reveal that the nurse is in fact the robot Galatea. Galatea eventually gives in with saying, "As the Great Andrew Martin once said, One is glad to be of service." She says this tearfully, implying that she had become unique over time after being exposed to Andrew and she too is well on her way to being human. Portia then dies hand-in-hand with Andrew. Courtesy of http://en.wikipedia.org/wiki/Bicentennial_Man_(film)