In science, they call it “convergent evolution.” In TV development, they call it a coincidence.

Each spring there are invariably a number of shows placed in development at different networks and studios that, at least based on a one-sentence description in a development report, sound a whole lot like some other show being developed elsewhere.

Tale of two dramas

Perhaps the most intriguing demonstration of that annual oddity this spring involves a tale of two dramas conceived, at least in part, as the next logical step after the extensive O.J. Simpson and Menendez brothers trial coverage: “Murder One” and “People V.,” both of which use the premise of following the intricacies of a single murder case – from the crime to the verdict – over the course of a 22-episode season.

Both shows have prominent creative pedigrees, though “Murder One” – which has a 13-episode commitment at ABC and comes from Steven Bochco, the dramameister behind such shows as “NYPD Blue,” “L.A. Law” and “Hill Street Blues” – has clearly garnered more of the spotlight.

“People V.,” meanwhile, is being produced for NBC through the network’s in-house division and Universal TV by Michael Chernuchin and Rene Balcer, both alumni of the NBC-Universal drama “Law & Order.”

Chernuchin, who is hoping to fill a six-episode commitment with his show, realizes that there are conceptual similarities but maintains that they’re overstated when such shows are reduced to facile abbreviations and log listings.

“Although the one-liners sound the same, they’re completely different shows,” Chernuchin says.

Location, location, location

One obvious difference will be geography: “People V.” is set in New York, “Murder” in Los Angeles. The Bochco show will also be approached principally from the perspective of one attorney, while Chernuchin says his will delve behind the scenes from all angles.

To some, those discrepancies may still appear superficial. Even so, the “Murder One”-”People V.” scenario is also hardly new and shouldn’t be considered much of a surprise in light of the roughly 120 concepts placed in development as possible primetime series, which, more than ever, are being designed by all the networks to appeal to the same youth-oriented demographic.

Producers and executives point out that while any number of projects may sound alike, the real magic lies less in concept than in execution. As a case study, they cite “Chicago Hope” and “ER” – two medical dramas set in Chicago hospitals that wound up in the same time period last fall.

Though the shows were lumped together in most pre-season press accounts, their differences were as notable as the similarities, with “Hope’s” flawed characters and more stately tone representing a contrast to the fresh-faced ensemble and breakneck pace of “ER,” which capitalized on all that medical-showdown hype and became the biggest first-year hit since “Roseanne” in 1988.

Pair of orphans

There were also two shows that made last year’s schedule that involved large broods of orphaned kids trying to get by on their own. Yet the two could have hardly been more dissimilar: ABC and Warner Bros.’ “On Our Own” was a broad comedy, while Fox and Columbia’s “Party of Five” was a sober teen-oriented drama. Missing parents, in fact, was a recurring theme throughout last spring’s development.

This year, there are the usual assortment of cop shows, science fiction pilots and projects involving high school, the last venue being a logical starting point to reach that prized young demo.

Another popular and overlooked theme, however, appears to be series set in or around television itself. Several are already on the air (“Home Improvement,” “Hope & Gloria” and “The Critic,” to name three), another has been ordered (“Live Shot,” a UPN ensemble drama set in a local TV newsroom) and more are in the works.

All pilots, however, should carry a disclaimer: Such descriptions don’t say much about how a show will ultimately turn out, and there’s plenty of room between a pilot concept about television, for example, and “The Mary Tyler Moore Show.”

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