He may not do it again for another year.
But during that moment in the "Twenty-Four Hours" studio, where he was being interviewd, David McCallum suddenly stopped being a two-dimensional spy character.
And on being shown laughing at his own film exploits, David placed the whole UNCLE business in proper perspective -- the biggest laugh show since Laurel and Hardy.
It's not so laughable for McCallum when he's on the set.
When he first signed for the show, he wanted to do all the stunt work himself. Executive producer Norman Felton compromised.
"We agreed," says Felton, "that David wouldn't do leaps from moving vehicles and long falls."
On at least one occasion David has cheated on the deal.
With his stunt man out of the way, he insisted in doing a cliff-top fight and 35-foot fall into a river.
It was a great sequence. But it caused several highly-paid Hollywood blood pressures to soar when they saw the rushes that evening.
Later, in Felton's office, McCallum was given the kind of reprimand that could only come from a man who saw visions of a million dollar hold-up in production if the star had suffered injury.
"David is particularly good in water," says Dick Geary, who is known as stunt coordinator of the series.
With 14 years of movie stunt work to his credit, Geary has been on "Man From UNCLE" right from the start.
He doubles for Robert Vaughn whenever the stunt is dangerous.
Another stunt man, Fred Waugh, doubles for Illya Kuryakin, blond wig and all.
A third stunt expert, Hugh Hooker, frequently plays the villian.
Some shots are so spectacular that as many as eight stunt men have worked in one 50-minute episode.
"McCallum is a stickler," says Geary.
"He won't let anyone else double for him but Fred.
"He says he's the only one who moves like him and looks like him from distance in the blond wig."
When David McCallum and Robert Vaughn do their own action sequences, Geary rehearses them move by move.
Neither Robert or David have to do special training to keep in shape.
The hard grind of the series is enough to keep them in fighting trim.
Sometimes they practice rope climbing, but that's about all.
In the early days of the series, though, McCallum studied ju-jutsu with an expert called Bruce Holloway.
With the cast of the "Man From UNCLE" enjoying their seasonal break from filming, stunt man Geary is still hard at work.
"With due respect to Napoleon Solo," he says, "I'm doubling for a more attractive and shapely personality just now."
"She's the latest UNCLE agent. A cute little number called Stefanie Powers.
"No doubt she'll get a lot of attention when the series 'The Girl From UNCLE' is screened in America this autumn."
Soon, too, Stefanie will face the kind of fan trouble that spells out success.
One aspect of it that David McCallum has found inconvenient is that he can no longer enjoy unrestricted use of his telephone at home.
Although his number is kept out of the directory, too many fans found it out and phoned him.
Now the number is changed frequently, and he tells it to very few people.
By mutal agreement, his mother sends him a cable from her home in London when she wants him to phone her from Hollywood.
She and her husband visited their son in California last August. He enjoyed showing them around, and his parents were amazed at his popularity.
"It's not so bad if he keeps moving," says his mother. "But if he pauses, even for a second, it's fatal. He's swamped by autograph books and hair-tugging youngsters."
David's mother dismisses the belief held by some that there is a real-life enmity between Illya Kuryakin and Napoleon Solo.
She met Robert Vaughn when she was in Hollywood and found him and her son on very good terms.
She took home with her to Hampstead a signed photograph of Robert, and it is now prominently displayed on a small table in her drawing room.
The inscription, penned by Robert, reads, "To Dorothy, my favorite Russian grandmother."