[2] Walter grew up with a love for science, and by the 1970s, became a head developer for a U.S. Government experimental research program called "Kelvin Genetics", alongside his long-time friend William Bell.

Walter and his friend William Bell conducted numerous experiments in the area of fringe science, including developing highly advanced weapons for the Army.

They constructed a "trans-dimensional window", a portal through which could view the other universe, which was more technologically advanced than our own (in "Peter", the Other Side appears to have already created digital cell phones by the year 1985).

[4] In the beginning of the first season, Olivia Dunham blackmailed the adult Peter Bishop to release his father from St. Claire's, in hopes of curing her lover, John Scott.

[1] During the episode, "Safe", Mitchell Loeb and a team of bank robbers used a vibrational dematerializing device to steal components from safety deposit boxes around the country.

The science team realized the safe belonged to Walter, and the components were all pieces of the machine he constructed in 1985 as his original plan to save Peter, but was eventually scrapped, which could "bring anybody from any time or anywhere".

[7] The organization Jones worked for, called "Zerstörung durch Fortschritte der Technologie" (ZFT), or, in English, "Destruction through advances in technology", was based on a self-published, anonymous manifesto under the same title.

Walter and Peter helped Olivia and Fringe Division stop Jones from crossing over to the Other Side to kill William Bell, and carried on with their lives, now happy as father-and-son.

[10] In episode 2x10, "Grey Matters", Walter was kidnapped by Thomas Jerome Newton, the shape-shifters' leader, and had his missing brain tissue re-implanted for a short time.

Heeding Walter's words, the man resets back to the day of his fiancé's death and holds her as a truck hits their car, killing them both.

Massive Dynamic and Fringe Division begin collecting the pieces and rebuilding the machine in a secure bunker, and Olivia is able to cross over momentarily to alert Peter of Fauxlivia's deception, who he had been romantically involved with.

[16] In 3x02, "The Box", Walter discovers that William Bell (who sacrificed himself in the season two finale to allow the others to return to their universe) left him a controlling interest in Massive Dynamic, making him CEO of the company.

[18] The science team visits the Massive Dynamic bunker where the doomsday machine is held, and it instantly activates because of the proximity to Peter, whose nose begins to bleed.

The reunited team began to seek out Olivia, who had been ambered while retrieving a vital component of Walter's plan, the Transilience Thought Unifier that could make sense of the pieces inside his brain.

Walter realized that it had always been his destiny and that he must sacrifice in order to save the world decides to take Michael through the wormhole as Peter, Olivia, and Astrid look on.

There are variations in their history as well, in part due to the William Bell of the parallel universe dying in a car accident as a child and thus never befriending Walternate.

[21] Leading into the show's present, Walternate has become the U.S. Secretary of Defense, overseeing a more militant Fringe division from his base on Liberty Island, though he has since separated from Elizabeth.

The purpose of the machine is later revealed during a scene at a pub; the observer strolls by, leaving behind a drawing depicting Peter being responsible for the apocalypse through the doomsday device.

Having captured the original Olivia, Walternate subjects her to memory implantation to make her believe she is Fauxlivia while trying to recreate the Cortexiphan drug and understand its properties, intending to execute her once his goals are reached.

Believing that now that Peter has chosen his side, he doesn't hesitate to proceed to activate the machine with the intent of destroying the prime universe and his son along with it.

However, Peter uses the prime-universe machine to create a "bridge" between both worlds, so that both can work together to heal their prospective universes, an alliance which Walternate grudgingly agrees to.

"[27] In his research, Noble noticed many prominent scientists had "complicated and interesting relationships" with music, causing him to create a similar bond between it and his character.

[28] In a November 2008 interview with the Los Angeles Times, Jeff Pinkner has called the character of Walter "incredibly fun to write for because he can say and do anything, which is a blast for a writer.

A mad scientist who has had parts of his brain removed by his partner, William Bell, and who spent more than 17 years in a psychiatric hospital for the criminally insane, Walter Bishop can best be described as an eccentric man.

While many parts of his intellect remain intact, he suffers from some degree of agoraphobia and has difficulty properly looking after himself, such that in both timelines he requires either Peter or Astrid to provide him with a basic level of care and supervision.

He has a great penchant for culinary arts, and can be found cooking and eating at odd times, for example, both in his lab while performing autopsies, and while naked in Peter's kitchen.

In line with his child like demeanor, Walter Bishop has a lovable innocence about him which is occasionally interrupted by tantrum like outbursts over largely trivial things.

His personality contrasts sharply with that of his parallel universe counterpart, "Walternate"; the Secretary of Defense, who is cool, collected, serious, and has a clandestine way about him which gives others the impression that he is untrustworthy.

While some of these differences are likely attributed to the fact that Walternate was never institutionalized nor had parts of his brain removed, there is evidence to suggest that the personalities of the two Walters began to diverge long before the death of Peter Bishop the boy, from the primary universe.

Maureen Ryan of the Chicago Tribune called Noble the series' "secret weapon" for his ability to "move with lightning speed between surreal goofiness and touching insecurity, often within a single scene.