FANCYCLOPEDIA II (1959, ed. Dick Eney) described the GDA thus:

"(Berry-Thomson) A sort of parody of the BBC's 'Goon Show'. It was built up from the name, which in turn came from a holograph letter from Ken Potter apparently adressed to "Goon Bleary" - ie. John Berry. The possibilities of this as a faname were immediately obvious. John and Art Thomson used 'Goon Bleary' to establish the GDA, as chronicled in its official organ, RETRIBUTION. GDA Ops are located in all portions of the globe, and will handle any conceivable problem and some you probably never heard of before in return for international currency. James White has written of a secret antagonist, Antigoon, who may doubtless be saddled with responsibility for any of the GDA's rare failures."
Here's the full account of the GDA's 1957 Worldcon gun-battle from James White's report in HYPHEN #19, with artwork by Arthur Thomson:


Cleveland GDA Op
Steve Schultheis

Sometime during the course or five courses of the luncheon somebody pinched the official gavel and clonker.

All the talking had made us hungry again, so a party comprising the Bulmers, the Kyles, Forry, Bert Campbell, Brian Aldiss, Steve Schultheis and myself went to the Italian restaurant again.

When I got back to the hotel Steve Schultheis accosted me on the stairs. His mouth held a lopsided leer, the brim of his hat was yanked down, and over his beautiful grey and silver speckled suit there hung a ghostly image of a Goon- type dirty raincoat. He said, "Lissen, White"- the GDA never pronounces the 't'- "Arthur and me has cooked somethin' up, see. We want ya up in the room in ten minutes, huh?" I shrugged and said "Oui." He said, "Yeah, just me an' Art and you." I said , "O.K.". You have to translate everything for some people.

Ten minutes later I walked into Room 43 to find. Steve and Arthur putting the missing gavel and clonker into an empty Kleenex box. I said, "Hah, so it was the GDA who stole the gavel...!" Arthur Thomson sprang to his feet, denying it hotly. Steve Schultheis poked tissue paper into the box to keep the contents from rattling and denied it coldly. Hissing in traditional Goon fashion he began to fill me in on the background.

The way Schultheis told it, he had seen the gavel and clonker disappear and had seized this opportunity to solve the case by offering Dave Kyle the services of the Goon Defective Agency to retrieve the missing articles. Kyle, in a weak moment, acccpted and handed over a cash retainer totalling one halfpenny, in sterling. Steve now wanted to make a production number out of the return of the gavel and, thinking of yours truly and his weakness for guns, knew just how to do it.

When I had heard him out I stated that I would participate in his plan on two conditions. One was that Antigoon, as the feearless champion of right and the scourge of the GDA, would never stoop to gavel-pinching, so it would have to be a pseudo-Antigoon who was blamed. Secondly, I must get the gun that fired seven shots, not one of the six-shooters. The GDA operatives agreed, and we got down to details.

Thus it was that at 8.30 I was seated in the main hall with a brief-case conaining the missing gavel balanced on my knee. The place was crowded and the crowd restive at the delay in the program. Carnell, who had already been briefed on the operation, mounted the rostrum. He delivered his lines well, announcing that the delay had been caused by the theft of the official gavel. The Convention could not proceed without it, he went on in a voice throbbing with suppressed emotion, but the services of a well-known detective agency...not the FBI but. one of similar repute... had been engaged to recover it. The organisation was the Goon Defective Agency and a report was expected at any moment.

At that instant a report rang out from the back of the hall where Goon Arthur Thomson, dressed in Mal Ashworth's military raincoat, fired a shot from a blank cartridge pistol borrowed from Shel Deretchin. Mal's raincoat was six sizes too big for Arthur, and all I could see of him was his shoes and the tip of his nose, plus a little hair. This first shot was the cue for me to jump to my feet. Immediately, Arthur shouted,"Stop, James White, vile pro and agent of Antigoon!" I snarled, pulled out the pistol lent me by Boyd Raeburn and returned fire, retreating down the ccntre isle with the brief case hugged to my side. In the confined space of the hall the firing was incredibly loud and dramatic. There was an instant's shocked silence, then mingled cheers and boos arose as those present chose sides in the battle.

I retreated slowly to the foot of the stage, then Steve Schultheis came blasting out from a side door. Caught in the deadly crossfire, I snarled, sneered and spat (I was out of ammunition by this time), then staggered, reeled and collapsed dramatically on the floor...after having dusted a section with my handkerchief ...with my head resting on the briefcase. Arthur Thomson dashed up, made a phoney little speech about the GDA always winning and plonkered me on the forehead to finish me off. Steve snatched away the briefcase so quickly that my head bounced on the floor, and I heard him handing the gavel to Carnell with a spiel about the glorious GDA. It was at this point that the carefully planned operation began to get all fouled up.

Ethel Lindsay, a nurse and a very nice person who has unfortunately been led astray by John Berry, was supposed to appear, then take my pulse and temperature, and help me stagger off the scene. Instead, Unethical Lindsay was standing on a chair with a GDA badge stating that she was Stephen F. Schultheis pinned to her chest, hooting and screaming "Down with Antigoon!" And Shel Deretchin, who had no part to play whatever except lending pistols, became overcome with excitement and dashed out and began dragging me off by the feet. At this point Arthur Thomson, out of respect for my suit if not for me, grabbed my other end and lfted me clear off the ground. I didn't think it was possible for the relatively diminutive Arthur Thomson to carry the heavy end of a fourteen stone weakling like myself, but he did it. For half an hour afterwards, however, he looked as if he had been shot 13 times instead of me.

The GDA-Antigoon gun battle was supposed to be a surprise item and it was. So much so that quite a lot of people in the lounge missed it. These, I found out later, had put it down to Sam Moskowitz having an attack of hiccups.