(CNN)"24: Legacy" is ending with more of a whimper than a bang. Along with "Prison Break," its tepid performance -- after the high hopes associated with a post-Super Bowl introduction -- indicates the limitations of programs built on TV nostalgia, and the missteps networks can make with reboots.
'24,' 'Prison Break' latest missteps with TV reboots
Fox has been especially aggressive in this regard, seeing such commodities as the solution to a marketing problem. Like the network's adaptations of the movies "Lethal Weapon" and "The Exorcist," "24" and "Prison Break" came armed with a pre-sold audience and plenty of name recognition -- a benefit not to be sniffed at in an age of media abundance.
As with Fox's year-ago revival of "The X-Files," however, the actual product left much to be desired. And while each project's history played a role in drumming up media attention and viewer sampling, the results appeared blunted in part by, for many, creative disappointment after the initial rush.
The two current shows actually followed different blueprints. "24" sought to reboot the franchise with a new central figure, played by Corey Hawkins, offering some callbacks to the original (welcome back, Carlos Bernard as Tony Almeida) while essentially functioning as an origin story on the character's journey from war hero to counter-terrorism agent.
"Prison Break," by contrast, followed a model closer to Netflix's "Full House" and "The Gilmore Girls" revivals by reassembling the cast, thrusting them into a new adventure that quickly fell apart dramatically because of its silliness.
What both programs have demonstrated is that the thrill associated with hearing those first strains of the theme music again can dissipate quickly when the show falls short of expectations.
While it's a bit too early to draw any serious conclusions about "Prison Break," "24's" trajectory lends support to the notion that the show misfired. After an inflated 17.6 million viewers following the Super Bowl, the thriller dropped to a respectable 6.2 million in same-day viewing, per Nielsen, for its time-period debut.
Since then, though, "24" has fumbled that kickoff: The audience has drifted downward, to about 3.3 million for its most recent outings, with a similar decline among key demographics.
Last month, a Fox executive admitted to being "a little sad" about the program's performance, telling Deadline that its renewal prospects would have to wait until the network sees all its new-series development before setting its fall schedule in May.
Hawkins wasn't the problem, and the idea of seeking to energize "24" with new blood appeared to be a sound one. The real lesson to be derived from both exercises is there's no substitute for quality execution, and absurd situations and lackluster writing made it feel as if the scripts were secondary to putting the familiar elements in place.
How the networks apply recent experience to future reboots remains to be seen. But as with "24," in TV, the clock is always ticking.
"24: Legacy" concludes its season April 18 at 8 p.m. on Fox.