Lieutenant Reginald Endicott "Reg" Barclay III was a highly talented Starfleet systems diagnostic engineer. He always appeared to be nervous and lacking in confidence, stammering profusely, and was known to be reclusive and extremely introverted. As a result of these traits, some crewmembers began to refer to him as "Broccoli."

Prior to Barclay's transfer to the USS Enterprise-D in 2366, he was assigned to the USS Zhukov. As a Lieutenant junior grade stationed aboard the Enterprise-D, Barclay had a tendency to spend more time inside the Holodeck where he was more confident and comfortable, than in real social situations.

(TNG: "Hollow Pursuits")

Barclay also suffered from severe transporter phobia, although he later overcame this psychological barrier.

(TNG: "Realm of Fear")

However, he developed arachnophobia as a result of these events. Later in 2375, Commander Worf and Chief O'Brien specifically mentioned nobody could forget him when remembering old friends on the Enterprise. He was remembered by O'Brien and Worf most for his extravagant "Three Musketeers" programs he invited the crew to join him in.

(DS9: "Image in the Sand")

During the Borg encounter of 2366-2367, Barclay worked on repairs with Sherman following the Enterprise's unsuccessful attempt to destroy the Borg cube using a burst of energy from the deflector dish.

(TNG: "The Best of Both Worlds, Part II")

Later that year, after an encounter with an alien probe, Barclay's IQ was raised to somewhere between 1200 and 1450. Unknown to Barclay, the probe's creators (known as the Cytherians) caused this so that Barclay would bring the Enterprise to them as was their custom of researching new races. Although he was returned to normal by the Cytherians, Barclay did retain a bit of the confidence and intelligence this experience gave him.

(TNG: "The Nth Degree")

In 2369, Barclay assisted Alexander Rozhenko in writing a holodeck program based on Deadwood, South Dakota during the Ancient West. Barclay included a prostitute in the simulation that Worf did not appreciate.

(TNG: "A Fistful of Datas")

Barclay later had a counseling session with Deanna Troi in mid-2370.

(ENT: "These Are the Voyages...")

Barclay was also a hypochondriac and was prone to self-diagnosis – he once thought himself to have transporter psychosis; on another occasion, he believed himself to have Terellian Death Syndrome. In 2370, a treatment for Urodelan flu, a mild illness, provided by Doctor Beverly Crusher activated a recessive gene that caused Barclay and the rest of the Enterprise crew to mutate into their former stages of evolution. Barclay transformed into a spider-like creature, ironic considering his fear of them. Once cured of this disorder, Crusher decided to name the new illness Barclay's Protomorphosis Syndrome as an homage to its first known patient.

(TNG: "Genesis")

Barclay transferred aboard the new USS Enterprise-E prior for the Battle of Sector 001 in 2373. He traveled into the past with the rest of the crew to April 4th, 2063, the day before First Contact, where he was able to meet one of his idols, Dr. Zefram Cochrane. He helped him repair the Phoenix warp ship after a Borg attack, and even got to shake Dr. Cochrane's hand.

(Star Trek: First Contact)

It should also be noted that the Lieutenant has a deep affection for cats, and for some reason the cats return this affection. Spot, Data's pet cat, found only her owner and the lieutenant to be suitable for her mercurial tastes.

To see Regs' career with respect to USS Voyager please click here