Desmond Miles, Subject 17

Desmond Miles - the protagonist of the Assassin's Creed and the descendant of a long line of assassins. He is initially forced to use a machine, called the Animus, by Abstergo Industries – the modern front of the Knights Templar – to relive the memories of his ancestor, Altaïr Ibn-La'Ahad, in their quest to locate the Apple, a Piece of Eden.

Eventually escaping with the aid of the modern-day assassins, Desmond
once again uses an improved Animus to explore the memories of a second
ancestor, Ezio Auditore da Firenze, so as to learn the ways of the assassins in a much quicker way than normal.

HISTORY:
Desmond Miles was born in an Assassin "hideout" in the desert, an enclave much like the city of Masyaf, where he was destined to be trained as an assassin. However, as he grew older Desmond later fled the hideout, claiming that "he wanted to see the rest of the world". He later told Lucy Stillman that he had no regrets over leaving his parents, because as far as he was concerned, they were his "wardens". At some point after leaving the hideout, Desmond became a bartender. Aware of the Knights Templar, and wanting to avoid both them and the assassins Desmond never used his
real name and paid only by cash. He was eventually found, however, by a
fingerprint needed for a motorcycle license.

In September 2012, Desmond Miles was kidnapped by Abstergo Industries, a pharmaceutical company and front for the Knights Templar, for use as a test subject in the Animus,
a device that can read the memories of Desmond's ancestors through the
"genetic memory" left behind in their descendants' DNA. At first Warren Vidic,
attempted to pry the information he wanted from Desmond's mind, but was
met with failure due to Desmond’s subconscious lack of confidence in
accessing that memory. As such Desmond was forced to relive the
memories of his ancestor from the earliest point at which he felt most
confident; this then allowed Desmond to simulate the experiences of his
ancestors. Whilst he claimed to be nothing more than a bartender, Vidic
reveals that they knew of his past as an assassin, forcing Desmond to
finally admit his past life. Vidic and Lucy Stillman
tell Desmond that they're trying to access a certain memory, but
Desmond's subconscious is restraining. Vidic warns Desmond that if he
refuses to assist them, they will induce a coma, continue their work,
and, when done with Desmond, leave him to die. Without much choice,
Desmond agrees to help them.
Desmond was made to explore the genetic memories of his ancestor – Altaïr Ibn-La'Ahad, a member of a clan of Assassins during the Third Crusade,
specifically Altaïr's experiences during the year 1191 – and over
several days does so under the watchful eye of Warren Vidic. During the
nights however, Desmond discovers that he is able to explore the lab he
is being held in, accessing the Animus computer and, after stealing his
keycard, the personal computer of Warren Vidic. Through these E-mails, Desmond learns of a Subject Sixteen
who had begun suffering from a "bleeding effect" due to prolonged
exposure to the animus, as well as tidbits of information from the
outside world. Eventually, with the aid of Lucy, the assassins learned
of Desmond's capture and attempted to liberate him, the gunfire being
heard through an intercom device, although the rescue attempt failed.
Vidic boasts that those assassins were in fact the last of the
assassin; their desert hidehout having previously been destroyed. Lucy
Stillman's actions, however, suggest otherwise, and when Desmond asks
if Lucy knows anything about his parents, she responds by saying that
she doesn't know, but that they probably escaped. During this
discussion, Lucy reveals herself to be a member of the assassins.
Desmond eventually achieves Vidic's goal, and discovers the
location of numerous Pieces of Eden. Executives of Abstergo Industries
order his execution, but his life is saved by Stillman's intervention,
who asks to keep Desmond alive for future reference. After the
executives leave, Desmond suddenly accesses the "eagle vision"
of his ancestor Altaïr, seeing Warren and Lucy for their true
allegiances, as well as countless scrawled messages and puzzles on the
floor of the main laboratory.

At the beginning of Assassin's Creed II
Desmond is still being held within the laboratory at Abstergo, an
unknown amount of time having past. One day, Lucy suddenly arrived,
covered in blood and demanding Desmond to get into the Animus before
Abstergo discovers what she's done. Desmond, rather confused, agrees
and, inside the Animus, experiences the birth of another of his
ancestors, Ezio Auditore da Firenze, a joint ancestor of his and Subject Sixteen's. He is quickly pulled out though, and both make their escape.
They were quickly spotted by Abstergo security forces and forced
into an engagement which Lucy quickly ends, allowing them to continue
on stealthily. The two soon enter a large open room filled with office
blocks, and lined with a large number of Animus machines, although
Desmond's question about them are met with silence. Desmond once
instinctively called upon his recently reactivated eagle vision when,
at the door to an elevator, a password was needed that Lucy did not
have. Once in the carpark the two are halted by yet more Abstergo
guards, but are able to overcome them and escape. Arriving at the assassin's hideout somewhere in Italy, Desmond was introduced to two more assassins – Shaun Hastings and Rebecca Crane
–who have been working with Lucy over the years. Lucy told Desmond that
they wanted him to become an assassin, and thanks to the bleeding
effect, they could achieve this in a matter of days, although it
required him learning the ways of an assassin through a new ancestor;
Ezio. Desmond agrees to help almost immediately, and is quickly plugged
in the Animus 2.0.
After learning the ways of the assassin through Ezio's memories
Desmond was retracted from the Animus, partly to test his retention of
the memories, but also to prevent the mental degradation that Subject
Sixteen had suffered from being in the animus for too long at a time.
Tasking him with initiating security protocols around the Assassin
hideout, Lucy left it to Desmond to work out how to reach them; just as
he begun, however, he started suffering vivid hallucinations of the
Crusader era. At first the vision were short, and that they were
nothing to worry about, but after completing the task Desmond was
incapacitated as the visions became more real. Taken back to Acre, Desmond followed the memories of Altaïr once again, this time without the use of the Animus, and watches as Altaïr and Maria conceive their first child, Desmond's next ancestor.
The next day, Desmond had recovered from the experiences and
returned to the Animus, neglecting to tell the assassins what had
happened. He continued the watch over the genetic memories of Ezio
Auditore, despite at one time being thrown out by a "corrupted memory
sequence". Eventually they learn that Ezio's arch-nemesis, the Templar
Grandmaster Rodrigo Borgia had, in 1492 become Pope Alexander VI, so as to gain access to yet another Piece of Eden, the Papal Staff and the Vault. As Ezio's story began to conclude, Desmond and the assassins watched deep within the Vault beneath the Vatican. Ezio found himself confronted by a hologram-esque "god" who called herself Minerva;
Minerva warns the assassins of the end of the world, as well as
retelling the story of the war between "Those Who Came Before", and
their human subjects. The assassins are shocked when Minerva addresses
Desmond by name, and it is revealed that Minerva is in fact talking to
Desmond through Ezio. Desmond is quickly pulled out of the
Animus though, seeing the three rushing to collect their belongings,
the Templars having found their location.
Immediately after getting out of the Animus, Lucy hands Desmond a Hidden Blade
with the Assassin's emblem on it, and asks for his assistance in
covering the escape. Making their way into the warehouse, Vidic
appears, flanked by Abstergo security official with the intent of
reclaiming Desmond. The two assassins fight off the Templars with
Desmond, now synchronized with both Altaïr and Ezio, performing
masterfully and slaying many with his Hidden Blade. With his entourage
eliminated, Vidic is left to confront Desmond on his own, but instead
retreats, promising that their victory is only temporary. The four
Assassins then flee north, and Desmond is hooked up to the Animus
inside the van and told to continue to search through his memories for
anything useful. As Desmond's hooked up, the other Assassins begin to
discuss the nature of Minerva and her talk.