There may be a short shelf life for the new Joss Whedon Fox series "Firefly," after Nielsen Overnight Metered Market Ratings saw a significant decline to already lackluster ratings.

The new science fiction show from the creator of "Buffy the Vampire Slayer" pulled in just a 3.6 rating/7 share. It didn't even come close to the show nearest to it in the ratings, "48 Hours Investigates" on CBS (5.0/9).

This comes after ratings for its series premiere finished at 4.1/8 in the overnights. In comparison, a new episode of "Buffy" pulled in a 4.0/6 on Tuesday while "Enterprise" grabbed a 4.8/7 in the overnights.

Also beating out "Firefly" for the hour was "Dateline NBC" (6.6/12) and "America's Funniest Home Videos" on ABC.

For the night, Fox finished in last place with a 4.0/7 rating. NBC was first with an 8.4/15, CBS was second with a 6.3/11 and ABC was third with a 5.0/9.