After working 2,000 people into a full-throated lather for the better part of an hour, Don Barris needs the audience to settle down a little. The excitable hype man for ABC's "Jimmy Kimmel Live" (picture Michael Chiklis on a steady diet of carbohydrates and Adderall) is trying to becalm the woots and cheers of a Wednesday afternoon crowd that's been enraptured by the likes of Marty McFly and Sen. Bernie Sanders because, as he puts it, "We're going to shoot a commercial now."

The spot in question is actually a custom integration for the health insurance service Cigna, which is using the Kimmel show's one-week residence at the Brooklyn Academy of Music as a launch pad for a new national ad campaign. Designed to remind viewers of the benefits of going in for an annual medical checkup, the "America Says 'Ahhh'" initiative will hit the ground running with its placement in three of this week's shows.

Once Mr. Barris has brought the ambient noise levels at BAM to a near-whisper, Mr. Kimmel begins the bit. Shortly into the standard desk spiel wherein he announces the night's remaining guests, the host is interrupted by a kerfuffle in the balcony at stage right, where the "JKL" band perches over the stage. As it turns out, an interloper in a turquoise T-shirt has taken it upon himself to sit in for band leader Cleto Escobedo, who has slipped away to indulge in a quick otoscopy in the "Cigna Checkup Room."

The gag elicits a respectable chuckle response -- the faux doc's Catskills-by-way-of-Flatbush line reading really sells the punch line -- and then Mr. Kimmel wraps the integration with a direct address to the audience. "Folks, we have a lot of fun," he says. "But Cleto right now is telling us just how important it is to get your annual checkup and take control of your health."

And that's the integration. On air, it clocks in at 90 seconds, which is effectively the same amount of time it took to shoot it. A standard 90-second commercial spot can take an entire day just to film, and that's before the raw footage lands in the editing bay. While the end result may not be anywhere near as polished as a vanilla TV ad (the Cleto usurper muffs one of his lines, although that in itself seemed to reinforce the idea that he isn't meant to be here), Cigna benefits from a lightning-quick turnaround, a significant cost savings, and the halo effect of an association with a popular late-night talk show host and native son. (In a nod to Mr. Kimmel's old stomping grounds, one of the onstage facades is a mock-up of the Mill Basin Deli.)

While there's no way of gauging how the Cigna integration will be positioned while it is being shot, it turns out that the insurance company has carved out an exclusive piece of real estate for itself. In the final broadcast, which airs on the east coast just five hours after the live taping wraps, Cigna boasts an entire standalone chunk of content.

For those watching at home, the integration follows an interview segment with Michael J. Fox, who shows off a pair of self-lacing Nikes and the official Marty McFly action figure. The actor earlier in the show had reunited with Christopher Lloyd in the guise of their old "Back to the Future" characters; both Marty and Doc are underwhelmed by how little progress the world has made in the intervening 30 years since they traveled in time to Oct. 21, 2015. Marty is particularly unnerved when Mr. Kimmel breezily informs him that most people now do the bulk of their TV viewing while perched on the toilet.

(As is the case with most men who were kids when the "Back to the Future" film were first released, Mr. Kimmel is most enthusiastic about the iconic DeLorean time machine Marty and Doc use to try and alter the past in order to improve Hill Valley's present. "How cool is this, to have the fucking DeLorean on the stage?" he asks, in an aside that is edited out of the final broadcast.)

The integration is immediately preceded by a traditional commercial pod that kicks off with a bumper ("portions of 'Jimmy Kimmel Live' are brought to you by Cigna…") that includes a prompt for the web site cigna.com/takecontrol. A 30-second "America Says 'Ahhh'" brand spot leads off the pod in the "A" position; after a barrage of messages for Subaru, ABC's "Wicked City," Dodge, the theatrical "Suffragette" and Absolut, the feed throws back to the BAM crowd and the integrated bit begins in earnest.

At the tail end of the broadcast, after Sen. Sanders has unveiled his Larry David impression, a 60-second Cigna spot featuring N*SYNC's Joey Fatone airs, and we have reached peak Brooklyn. Including the two standard spots, the integration and a pair of brief bumpers, Cigna paid for 195 seconds, or three-and-a-quarter minutes, of airtime in the one-hour broadcast.

While Cigna did not disclose the cost of Wednesday night's integration, the clutter-free environment in which it ran and the imprimatur of the Kimmel creative team ensures that the company is paying a premium when compared to the standard unit cost for 30-second spots. Buyers estimate that the price of reaching Mr. Kimmel's younger, hipper audience is around $25,000 per 30-second sliver of airtime.

Cigna's overall TV budget for 2015 is $27 million.

If the Kimmel integration was arguably the most visible component of Cigna's Wednesday night ad push, the company also locked in an integration on ABC's "Good Morning America." Another baked-in execution is planned for the network's daytime chat show, "The Chew."

Cigna's promotion of preventative care and wellness will continue through December. "We're using an innovative and creative platform to help people across America take advantage of preventive care, starting with a basic annual checkup," said Stephen Cassell, Cigna's global branding officer. "Lecturing, scolding and scaring people into taking action don't work. Cigna is taking a light-hearted approach to show how simple, easy and quick a basic checkup can be. We want to demonstrate that it is not only necessary, but also maybe a little bit fun."

Back at the "Jimmy Kimmel Live" taping, Mr. Barris asks for one last interval of silence while the crew readies the final shot of the night. Mr. Kimmel has long since departed -- the host is in a rush to go watch his beloved Mets secure their first trip to the World Series since 2000 -- but in a bit of TV trickery, the director needs to get a few rim shots on tape. Alone up in the balcony, the drummer obliges, tapping out an old-school percussive response to a joke that hasn't been told. The rim shot eventually finds its way into Mr. Kimmel's opening monologue, where it is used to sweeten a groaner of a one-liner about "Star Wars: The Force Awakens."

No such sleight-of-hand was required in the Cigna campaign, which was spearheaded by McCann New York for the creative and OMD Worldwide on the media buying.