Walter "Radar" O'Reilly
Radar O'Reilly
Gary Burghoff as Radar O'Reilly
M*A*S*H character
Vital information
Rank: Corporal (E-4), U.S. Army
Job/Role in Unit: Company Clerk for the 4077th M*A*S*H
Hair Color: Burnt Auburn
Eye Color: Grey
Height: 5'4"
Weight: 135 lbs.
Family/Personal Information
Birthplace: Ottumwa, Iowa, U.S.
Nationality/Race: American/Caucasian
Relatives/Children: Mrs. O'Reilly (mother)
Ed O'Reilly (uncle)
First appeared in: M*A*S*H Novels
MASH (film)
Last appeared in: Good-Bye Radar: Part 2 (TV series episode)
Appeared on/or in: M*A*S*H TV Series
W*A*L*T*E*R special
Played by: Gary Burghoff

Corporal Walter Eugene "Radar" O’Reilly is a fictional character in the M*A*S*H novels, film, the television series, the television movie W*A*L*T*E*R and two episodes of the series After M*A*S*H. The character was portrayed by Gary Burghoff in both the film and on television — the only actor from the film to reprise his role on television, aside from G. Wood as General Hammond, and the never-seen PA announcer voiced by Sal Viscuso (though this is debatable).


The novel establishes that Radar was from Ottumwa, Iowa, and dreamed of joining the army right after high school. He was endowed with apparent extra-sensory perception, appearing at his commander’s side before being called and finishing his sentences. He also had super-human hearing, able to hear incoming helicopters before anyone else. It was these abilities that earned him the nickname "Radar".

His father, who had been 63 when Radar was born, was deceased. Radar's mother Edna lived on the family farm and his Uncle Ed helped out on the farm and served as his father figure.

According to the beginning of the novel, Radar joined the Army in hopes of becoming successful in the Signal Corps, but was assigned to be an orderly in a Mobile Army Surgical Hospital (MASH) instead.


Radar's character started off as worldly and sneaky, a clerk who carried with him at all times a pocketful of passes for any potential scam that might arise. He also sold tickets to the male members of MASH so they could take turns sneaking looks through a peephole in the nurses' showers and also used his camera to sneak pictures of the nurses showering. He also won over $800 in poker playing with members of MASH and dismantled a jeep and smuggled it home piece by piece. He once conned the entire company of MASH 4077 into buying a pair of wing-tip shoes--although he was once conned himself into spending over $50.00 for a improved writing course by mail--which nearly drove Col. Potter crazy trying to read the daily reports. He was known for his tremendous appetite for heaping portions of meat. He was also not averse to drinking Col. Blake's brandy and smoking his cigars when the colonel was off-duty. This character was apparently not wholly to the writers' liking and he later became a naive and trusting farm boy, a vegetarian, and cigars and strong liquor made him ill or dizzy. His favorite beverage was grape Nehi soda.

Relationship with senior MASH staffEdit

Radar was often portrayed as a friendly but very naive young man from the Midwest. As a symbol of how young this man was when he got to Korea, he slept with a teddy bear. He related well to children and sometimes spent time with the Korean orphans in the area.

Radar had a rough start as clerk at the 4077th, where it seemed he couldn't do anything right. The unit's commander, Lt. Col. Henry Blake, took him under his wing. Eventually, the young man became an excellent clerk, often balancing out Lt. Col. Blake's occasional silliness, with the near-magical abilities to get whatever the unit needed. Throughout much of the series he was more or less the glue that held the 4077th together, keeping the unit running like a well oiled machine.

Blake and Radar grew very close, and it was Radar who tearfully announced Blake's death over the Sea of Japan. While Radar needed some time to adjust to the new Col. Potter, he eventually became very close to Potter as well. Radar was very fond of animals and raised several during his duty at M*A*S*H. For Col. Potter's anniversary, Radar gave him a horse that he, Hawkeye and B.J. rescued. Col Potter refers to the horse as a male during this episode. Throughout the rest of the series, the horse is referred to by name, Sophie, a mare.

Radar idolized Hawkeye Pierce, but the two had a falling out after Radar was injured during a trip to Seoul, after Hawkeye convinced him to go there to lose his virginity. Overwhelmed by shock and guilt, Hawkeye spent a night binge drinking, then had to leave the O.R. the next day to throw up (which he'd never had to do before). When Radar questioned Hawkeye about this, Hawkeye blew up: "To hell with your Iowa naïveté... and while we're at it, the hell with you! Why don't you grow up... you ninny?!". When Hawkeye returned to apologize, Radar's response was, much to the horror of the nurses, "Oh yeah? Well you can forget it. Just forget it! To hell with me, huh? To hell with you! How do you like that?!" and then threatened to punch Hawkeye if he ever said anything bad about Iowa again. The two made up later at Col. Potter's prompting, and afterward their relationship was on more of an equal footing, with Radar outgrowing his hero worship.

Radar's short stature was a frequent source of humor during his tenure, with Hawkeye and the other doctors teasing him for his lack of height. At one point, Radar actually bought shoes that came with lifts so that he could appear taller. The shoes almost made him eye level with Major Frank Burns.

Under Col. Potter, his scrounging and semi-legal activities are strongly curtailed, seemingly out of respect for his commanding officer.

Radar's given first name is revealed in the series when he asks a patient, who believes he is Jesus Christ, to bless his teddy bear. He then blesses Radar, who corrects him with "Walter."

Relationship with womenEdit

One of the heavily developed themes throughout the series was Radar's fairly clumsy efforts to relate with the various women he meets. Radar was portrayed as a virgin and very naive around matters of love although he has a fiancee (who broke up with him in the Season 1 episode Love Story). His naivete made him an occasional romantic target of the camp's nurses such as Nurse Gilbert (Bobbie Mitchell) in Dear Dad...Three and Nurse Baker (Lynne Marie Stewart) in Lt. Radar O'Reilly.

In other episodes where Radar tries to chat up a nurse, they are either not interested or something usually goes wrong. In Love Story, he must hurriedly learn to fake knowledge about classical books and music in order to impress Nurse Louise Anderson. In For Want of a Boot he secures a date with Nurse Murphy only to be thrown out. In Springtime, he becomes interested in Nurse Louise Simmons but gets more than he bargains for. Late in Season 7, Radar finally succeeds in getting a date with Lieutenant Linda Nugent when he learns to be himself.

Leaving M*A*S*HEdit

In the first three seasons of M*A*S*H, Gary was in every episode of the season. After season five, doing the series became a strain on Gary's family life, and had his contract changed to only doing 13 episodes per season out of the usual 24 (during these times, the character of Radar was usually on R&R). By season 7, Gary started experiencing burn-out and decided it was time to move on, despite co-star Mike Farrell trying to persuade him to stay on the grounds that his career would not recover. Because of that, the producers originally planned to end season 7 with Radar leaving, but CBS didn't want to do that. Instead they wanted Gary to come back during season 8 to do a special 2-part goodbye show.

In Good-Bye Radar, news arrives that Radar's Uncle Ed has died. (We never learn whether Uncle Ed was the brother of Radar's mother or her brother-in-law.) Potter immediately arranges a hardship discharge for Radar so that he could go home and help his mother on the farm. However, when Radar sees that the unit is in dire straits because they have no working generators, he decides that the 4077th needs him more than his mother does.

Pierce and Potter try to convince Radar that he is making a mistake, but it takes Klinger's swindling a generator from supply to convince him that the 4077th will survive without him. As a way of saying that Radar came to Korea as a boy and went home a man, he left his teddy bear behind (as Dr. Sidney Freedman predicted he would in the episode War of Nerves), leaving it with Pierce.

Radar was referred to several times since leaving. On the next episode after leaving, Peg Hunnicutt writes BJ and says that their daughter Erin saw Radar at the airport in San Francisco and called him "Daddy". BJ was devastated that the first person to be called "Daddy" by his daughter was someone else. After hard times hit the farm, Radar took up a second job, working in the town's general store, as well as working the farm. So when a young Korean farmer lost his family, the gang sent him to Iowa to work on Radar's farm to help out.

In the 1984 television pilot, W*A*L*T*E*R, Radar moves to St. Louis, Missouri, leaving Ottumwa, Iowa, after losing the farm to competing government subsidies and a failed crop season. After finding a place for his mother with his Aunt Lucille, he leaves the "Radar" nickname behind (now just being known as Walter O'Reilly) and joins the police department. Set in the mid-1950's in St. Louis, his gentle manner and resourcefulness make him good at dealing with the public. However, the show was never picked up as a regular series.

Teddy BearEdit

Radar's teddy bear had originally been found on the set by one of the actors. Throughout the series, Radar was known for sleeping with a teddy bear. This was added by the creators to symbolize Radar's youth and naïveté; it was also the source of several jokes throughout the series—which collectively formed a recurring joke in itself. In the second to last episode (actually, the last episode filmed), As Time Goes By, Pierce added the teddy bear to a time capsule with several other items from the camp including one of Henry Blake's fishing lures and a broken fan belt from a helicopter. Hawkeye said, "Let [the bear] symbolize all the boys who came over here that left as men."

Radar's teddy bear was originally thought to have no name, but in a letter to Ken Kessler (who ran a radio show where the question of Radar's teddy bear's name was brought up), Gary Burghoff said that his teddy bear's name was Tiger. On July 29, 2005, the teddy bear used in the series was sold at auction for $11,800.


  • Big Bird of Sesame Street has a teddy bear named Radar, perhaps a tribute to Radar O'Reilly's teddy bear and Radar himself.
  • Radar was only in his late teens, but Gary Burghoff himself was almost 30 at the time the series began. Audiences were generally fooled by his short stature, boyish appearance, and prepubescent voice.
  • Gary Burghoff's left hand is slightly (but visibly) deformed, which would ironically make him unfit for military service. This was covered up in the series by Radar holding a prop such as a clipboard in that hand or simply putting it in his pocket.
  • Having played the character in the feature film, the television series, and two of its spin-offs, Gary Burghoff is the only actor to portray Radar. Trapper John, M.D. is the only version or spin-off of M*A*S*H in which Burghoff does not appear.
  • O'Reilly Media maintains a blog about new technologies entitled O'Reilly Radar, which has the domain name
  • With Radar's departure from the show, Hawkeye Pierce, Margaret Houlihan, and Father Mulcahy were the only remaining characters on the M*A*S*H TV series with ties to the 1968 novel and the 1970 movie.
  • Burgoff also played Mrs. O'Reilly in one episode in a home movie, dressing in drag.
  • Burgoff was also the first adult actor to appear nude from the rear on broadcast television. In the episode The Sniper, Burgoff's towel fell off too early, revealing his bare buttocks for a noticeable amount of time.


  • "Lt. Col. Henry Blake's plane was shot down, over the Sea of Japan. It spun in. There were no survivors."
  • "Cows are people too!"
  • "I know he's not real, but we're very close."
  • "I'm Walter."
  • "Hey, we got rain here! You too? Wonder why the army ordered that?"
  • "You heard me! H-E-double toothpicks!"
  • "My doctor back home says I gotta' eat lots of greens. I have a deficiency of malnutrition."
  • "You better believe it mister, or I'm dead where you stand. (points his teddy bear as if it were a gun; the sound of a gunshot is heard at the same time) My bear went off!"
  • "Permission to cover my nakedity, sir."

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.