"Fashion Show," which some have labeled a "Runway" knockoff, debuted May 7 with 458,000 viewers in the female 18-to-49 demo.

Ratings then rose for the second episode in "live plus same day" performance. But last week, viewership dropped 36% to 369,000 among women 18 to 49.

An inauspicious signal: the decreased ratings May 21 came as the show aired in the Thursday 10 p.m. slot opposite repeat dramas on ABC and CBS (NBC had a new episode of "Southland").

The amount of total viewers for "Fashion Show's" first three episodes have followed a similar pattern -- an upswing for episode two and then a notable drop-off last week. Total viewers in week two were 906,000 ("live plus same day") -- but fell to 734,000 last week. The fourth episode airs tonight.

A Bravo spokesperson said the network is pleased with the show's performance. It's possible that ratings will mirror a "hockey-stick-shaped" graph for the series, with dips now followed by a rise leading up to the finale (that date has not been set).

Like "Runway," "Fashion Show" features aspiring designers competing under intense pressure, with one contestant eliminated each week. "Runway" was Bravo's highest-rated show ever, averaging 2.1 million 18- to-49-year-old female viewers last season.

Any suggestions that "Fashion Show" would come close to matching "Runway" in a first season may be questionable -- especially without "Runway" headliners host Heidi Klum and the engaging Tim Gunn.

"Fashion Show's" May 7 premiere did crush "Runway's" December 2004 debut, which drew only 144,000 women ages 18 to 49 -- a sign of how much "Runway" grew through its fifth season last fall.

Still, Bravo's much higher ratings and revenues than five years ago arguably gave it a stronger launch pad for a new show now. And "Fashion Show" no doubt benefited from the publicity surrounding its relationship to "Runway."

Bravo developed the similar series while it was mired in a high-profile legal battle with Lifetime over the rights to "Runway." Bravo's parent NBC Universal eventually settled the case, allowing "Runway" to shift to Lifetime in late August.

Vis-à-vis "Runway's" Klum and Gunn, it remains to be seen how much the audience will warm to "Fashion Show" judges/hosts Isaac Mizrahi and Kelly Rowland.

The "live plus same day" ratings for "Fashion Show" do not represent its total amount of unique viewers -- not with DVR-enabled viewing and multiple opportunities for people to catch episode repeats.

One sign that there may be many "Fashion" seasons to come: Even the low adult 18-to-49 ratings on May 21 were on par with Bravo's season-to-date average in that demo.

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