However, Fleinhardt had an addiction with card counting during his years as an undergraduate, which he feels ashamed about and has compared his discomfort during field research at a casino as being at the event horizon of a black hole; this was discussed in "Double Down", an episode that focused on a gambling ring.

Dr. Fleinhardt has worked on building a space telescope for DARPA in the past, but it was weaponized against his wishes as part of the star wars missile defense project.

When Larry suggested a neural imbalance may be the cause of his lack of dreaming in "Hot Shot", Charlie thought the notion would explain a lot about his friend.

The "Doc" even had his own Eureka moment in "All's Fair", wherein he applied fluid mechanics to the analysis of footprint slabs he submerged in a jacuzzi only to determine, from the relative displacement of water by each indentation, that the suspect to a murder had a short right leg — a discovery that discounted a particular individual from guilt — and ran to the streets dripping wet in a robe, screaming that it was Archimedes all over again, only to forget where he put his clothes the next minute.

Apparently, as mentioned in "Backscatter", Fleinhardt is awful when it comes to geography — he called to ask if the string theory convention he was already at was in St. Louis or Cleveland, when it was actually in Minneapolis.

Meanwhile, he has realized his affections for Megan, and describes to his confused friends, the Eppes family, that they are closer to understanding the mystery of gamma-ray bursts than his feelings in this matter.

In "Long Shot" (episode 3x06) they create a schedule for dinner and a movie every other Friday, lunch on Wednesdays, and a monthly wild card that Megan can use at her discretion.

After selling his home, Fleinhardt has for some time since been living as somewhat of a vagabond, finding shelter in his office, his car, hotels and friends' places, and often sleeping on couches or in CalSci's steam tunnels.

In the episode "Brutus", it is revealed that Larry's divestment of his personal property was in anticipation of being selected as a payload specialist on the International Space Station.

His work on the cosmic microwave background has some relevance to the NSA's satellite signals technology and he was contacted by this agency last September to serve as an alternate for the recently detained Professor Johannes Igby, a rival physicist who created the now proven (though initially contested by Larry) Igby's Law to redefine the gravitational flux motivated by sound wave propagation in Bose–Einstein condensates and a candidate on the short list for the National Medal of Science award.

Megan seems to be the only one who has some idea of this situation that explains his unorthodox living style and prior mystifying absences (to go to Houston), though his friends had thought that these elements were just part of Larry's quirks.

Charlie is in disbelief over the matter and is distraught at the potential of a temporary loss of his friend, even worrying about Larry's safety as he boards the next Space Shuttle to the International Space Station for a six-month stay 250 miles above Earth; even Larry is mindful of the risk involved in sitting atop 2 million liters of combusted liquid hydrogen and oxygen.

He remands his few prized possessions, including a miniature model of his classic car, a stash of jazz recordings, a Newton Lacy Pierce Prize in Astronomy by the American Astronomical Society he received long ago, a Science Journal International diploma, and an old t-shirt he wore on the first day he posited causal solutions to ultrahyperbolic wave equations and, more memorably, when he vanquished Professor Muskrave at the CalSci Texas Hold'em Tournament, to his closest friend, Charlie.

In "Killer Chat", Larry's fulfillment of his dream is called into question as a rival in Massachusetts (at MIT) told NASA that he had been living in the steam tunnels.

While Charlie is ecstatic to see his friend and inquires about the awe in celestial phenomena and his LISA data, Larry is detached and not ready for complex social interactions such as a CalSci welcoming party, although he wants to have dinner with him.

Dr. Fleinhardt asserts that he is only going to teach one seminar the whole academic term and is going to continue the search for the Higgs boson, the 'God Particle', with the DØ experiment team, as he received a "tantalizing offer" from them.

Amita further points out that this is in line with his spiritual endeavor, after she says that he wants more from life than his recent habit of just walking in gardens, and he shares the same view.

He and Amita spend at least twenty hours a week doing DØ research, though, in "End Game", Larry has a crisis of faith regarding his Higgs boson work, wondering if he is a hypocrite to be searching for something he may not want to find.

In "When Worlds Collide", it is revealed that Megan is leaving the FBI to go back east, to which Larry says that their relationship has never depended on geographic proximity.

With Don, Larry advises Charlie to stay clear of the duplicitous Jane Karellen (Nancy Travis), head of DARPA special projects, due to his own experience with her (including romance), and they confront her ("First Law").

Alongside Charlie and Alan, he has been coaching the struggling CalSci basketball team with his physics calculations, but he is not above shouting and even getting NBA players to achieve a win ("12:01 AM").

His equations, spanning supersymmetry, string theory, supergravity, and cosmology and dating back from his days at Princeton, appear on the walls of CalSci's underground level with a Hindi mark saying सब बेटे के लिए (All for the Son) thereby passing them on to Charlie.

After buying tickets to visit one of several locations, they fly out of his car, and as he goes to retrieve them, he spots several acres of land for sale with a view of the stars that makes him pause.

Refreshed, Fleinhardt has a clarity of thought that excites Charlie and upsets the unconvinced Alan, as his equal in chess has now become like Garry Kasparov.

[3] In episode 4x12, "Power" (air date 1-18-2008), Fleinhardt accepts an invitation to join Fermilab's Dzero collaboration, working to solve the mysteries of the universe and find the Theory of Everything.

Co-writer Nick Falacci offered the following explanation for this plot development: "Like real-life physicists, Fleinhardt hit a roadblock trying to create an 11-dimensional supergravity theory.

[9] Toni Fitzgerald of Media Life Magazine stated that MacNicol, as Larry, "brings a welcome eccentric flavor to "Numb3rs" that's missing from "CSI" and its ilk".