TUNED IN

What if there were a cigarette that could deliver the pleasure of smoking without the danger of inflicting emphysema, cancer and other health problems?

That’s a question the tobacco industry has been grappling with for decades.

PBS’ “Nova” (8 p.m., KCET) tonight examines the difficulties--both scientific and political--that have plagued the search for a safe, or at least safer, cigarette.

It’s a fascinating account that won’t win the tobacco industry any new respect for the toxic product it produces but that will surprise a lot of people.

Considerable time, money, manpower and creativity have been spent in exploring how to make something less lethal.

The efforts go back to the 1950s, when Lorillard first put filters on Kents. Alas, using asbestos in the filters turns out not to have been a real plus in terms of increasing health benefits. But you can’t say the company didn’t try.

The industry’s research and development have continued, as we see here, with attempts to lower tar and nicotine levels, to change the tobacco curing process, even to develop a cigarette that burns less hot--electrically, for instance.

Several companies are test-marketing “reduced-risk” brands now, but “Nova” suggests that caution is in order: Given the tobacco industry’s record, it isn’t to be trusted in leveling with us about how much safer those cigarettes truly are.

Surf Report

SERIES The Sunnydale gang plans to bring “Buffy the Vampire Slayer” back from death in the show’s season premiere (8 p.m. on UPN).

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SPECIALS

In another installment of “History vs. Hollywood” (8 p.m. History), David Mamet’s “Hoffa” traces Jimmy Hoffa’s life.

“Atlantis Reborn” (10 p.m. TLC) pursues the theory that the mythical lost continent may have been the cradle of civilization.

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MOVIES

Dustin Hoffman stars as a recent grad who takes interest in his parents’ friends in “The Graduate” (7 p.m. TCM).