(Pictured: the Village People onstage in the summer of 1979.)

On the weekend of July 7 and 8, 1979, American Top 40 counted down the Top 40 Hits of the Disco Era, covering big hits on the radio and in clubs over the preceding five years. It’s all killer and no filler. Seven songs from Saturday Night Fever are on the show: “How Deep Is Your Love,” “You Should Be Dancing,” “Stayin’ Alive,” and “Night Fever” by the Bee Gees, “Disco Inferno” by the Trammps, “A Fifth of Beethoven” by Walter Murphy, and Yvonne Elliman’s “If I Can’t Have You.” (The latter might be the best song on the show, if it’s not “Stayin’ Alive,” or “Miss You” by the Rolling Stones, which sounded great in this context.) As an individual performer, Donna Summer has the most songs on the show, five: “Love to Love You Baby,” “Last Dance,” “I Feel Love,” “Hot Stuff,” and “MacArthur Park.”

“MacArthur Park” was Summer’s first Hot 100 #1, in the fall of 1978, but after the twin barrage of “Hot Stuff” and “Bad Girls” a few months later, you stopped hearing it much. “Bad Girls,” which is not on the list, would make #1 the week after this show aired and end up the longest-running #1 hit of Summer’s career—something the AT40 staff could not have predicted when they were researching, scripting, and recording in the spring and early summer.

The show is packed with informational factoids. At one point, Casey says that the popularity of disco means that everybody is doing it, referencing the forthcoming Ethel Merman Disco Album and a disco version of “Take Me Out to the Ballgame” by baseball announcer Harry Caray. (The latter is quite something. Harry sings, but he’s swamped by the female singers with him.) Elsewhere, Casey mentions that disco DJs like to play a slow song every 45 minutes to one hour, and lists the most popular slow-dance numbers: “How Deep Is Your Love,” “Three Times a Lady” by the Commodores, and “Reunited” by Peaches and Herb. All are heard as extras on the show.

Other extras include “Rock the Boat” by the Hues Corporation, widely considered to be the first disco record to hit #1; “The Twist,” the most popular dance hit of all time; “The Hustle,” the most popular song named for a disco dance step; and “Disco Duck,” which Casey cites as an indication that disco is here to stay and more than just a fad. Also included: “San Francisco” by the Village People, which Casey says is the most successful record in clubs never to make AT40, because it was never released as a single.

Casey offers quotes from record executives, journalists, and broadcasters discussing the disco phenomenon. Several of them suggest that disco’s popularity has a lot to do with people’s desire to escape economic and social hardships. Others portray it as a communal art form in which the audience is the star. He mentions a couple of different times that there are 20,000 discos in America, which seems like a lot. I suspect that number includes any small-town bar or Holiday Inn lounge that put up a disco ball or had a DJ rig. He name-checks a doctor who claims to be a practitioner of something called “discogenics,” which treats injuries people get from dancing. (There is a real thing called discogenic pain, which is caused by degenerating discs in the spine, regardless of whether the condition is caused by too much boogie-ing.)

But despite all of its undeniable bangers, the show has an odd vibe, and it’s because of Casey himself. It sounds like he’s not entirely present in the moment. He zips through his scripted lines in perfunctory fashion, like he’s trying to get the show done, just another item on a jam-packed To Do list. (What we know of Casey’s career as a voiceover talent by 1979 indicates that certainly could have been the case.) The show largely lacks the feeling of one-to-one communication that made Casey such a pleasant companion on the radio.

AT40 compiled its list based on Billboard chart data and a survey of disco DJs across the country. The #1 song is “Le Freak” by Chic, which spent six non-consecutive weeks at #1 as 1978 turned to 1979. (Like “MacArthur Park,” “Le Freak” would soon be surpassed in importance within a few months by another of its own performer’s hits: “Good Times.”)

When this show aired in the summer of ’79, the disco tide was already going out a bit after peaking in the spring. But as a snapshot of an all-consuming cultural moment, you can’t do better.