NBC launched a new live program that sent Neil Patrick Harris careening through an hour of pranks, live stunts and Vegas-style extravaganza as the network pushed forward in its quest for a new hit for its fall schedule.

“Best Time Ever” evoked everything from the old 1970s chestnut “Battle of the Network Stars” to the “What’s Up With That?” sketch on “Saturday Night Live” (in which cast members dance, sing and jump about with increasing randomness) with a singular conceit of having Harris weave together elements as disparate as Oscar-award winning actress Reese Witherspoon doing a turn as a show announcer and a cameo by comedian Carrot Top – all on the fly.

Based on the series “Saturday Night Takeaway” that airs on Britain’s ITV, “Best Time Ever” has NBC playing to what in recent years has been its strength: live (and live-to-tape) spectacle. The network’s schedule is largely propped up by programs like “Sunday Night Football,” “The Voice” and its late-night franchise “The Tonight Show Starring Jimmy Fallon.” And while hit scripted fare has been hard to come by, other than “The Blacklist,” NBC has found some success with live pageantry based on adaptations of Broadway musicals aired at holiday time. The network also intends to air the sitcom “Undateable” live on Fridays, and has considered plans to return to a variety show led by comedienne Maya Rudolph that got a brief test run in May of last year, this time with Martin Short as a co-host.

Harris led the new gambit Tuesday night. He unveiled to various audience members how he had surreptitiously followed them. He picked viewers at home to indulge in a karaoke version of Gloria Gaynor’s “I Will Survive” (with Gaynor singing on set). He raced Witherspoon on a daring high-in-the-sky skywalk-and-zipline contest that appeared to fluster the actress. Dancer and singer Nicole Scherzinger, who will serve as a co-host of sorts throughout the program’s early fall run, added humor and even a teasing dance for audience members.

Whether it all came together is a matter of personal taste. The program was as perplexing as it was distracting , with viewers led through a parade of guests  – Carson Daly! the judges from “The Voice”! Some kid Harris referred to as “Little NPH!” – and a panorama of bits that also included a game-show element called “Get Lucky” and a frenzied finish that involved bar tricks, dancing and pogo sticks.

NBC appeared to scale back some very ambitious advertising plans it had for the show. During its upfront presentation in May, the network hinted at an idea that would allow an audience member or viewer to “win the ads,” or win the products being advertised during the program. But the only place any sales pitch manifested during “Best Time’s” debut was in the “Get Lucky” segment, which gave an audience member the chance to win prizes that had been provided by companies including Hilton, Jeep and Kohler.

The show aired at 10 p.m. Tuesday night, but is slated to move to 8 p.m. on September 29, where it will have to draw a crowd all by itself, without the benefit of a lead-in. Harris has already taken a great deal on his shoulders, and soon he will have to carry even more of a burden – live.