Fresh Air with Terry Gross

Johnny Carson walked away from The Tonight Show, after 30 years at the top of the late-night ratings, of his own volition. And except for a few fleeting TV appearances after he retired, he never looked back — and never went back. When filmmaker Peter Jones would send an annual letter to Carson, asking for his cooperation in a TV biography of him, the answer was always no. One year, Carson went so far as to explain why: Let the work, he said, speak for itself.

Friday marks the 25th anniversary of the day Fresh Air became a daily national NPR program. Before that, the show was broadcast only on WHYY in Philadelphia. How long ago was May 11, 1987? On Fresh Air's first edition, TV critic David Bianculli reviewed the finale of the TV series Hill Street Blues.

Two score and four years ago, I'd fly home from fourth grade for the 4 p.m. broadcast of Dark Shadows. In 1968, vampires and werewolves weren't mainstream — the era's horror films mostly played drive-ins — yet here on TV was a daily horror soap opera.

In 1966, creator Dan Curtis conceived of a show that was Gothic but nonsupernatural, like Jane Eyre. But after less than a year, with Dark Shadows on the verge of cancellation, he threw a Hail Mary pass, directing his writers to add a vampire. In came Barnabas Collins, played by Canadian actor Jonathan Frid, a villain meant to be staked through the heart after a few months.

If you're sitting at a desk reading this article, take a minute and stand up. That's the latest advice from New York Times Phys Ed columnist Gretchen Reynolds. In her new book, The First 20 Minutes, Reynolds details some of the surprisingly simple ways you can combat the effects of a sedentary lifestyle.

Federal health guidelines recommend 30 minutes of moderate exercise — such as walking or jogging — every single day. But new research shows that even regular exercisers may not be doing enough to counteract the health hazards of sitting down at a desk all day long.

This interview was originally broadcast on May 9, 2011. In The Garden Of Beasts is now available in paperback.

In March 1933, President Franklin Roosevelt approached politician James M. Cox to offer him what should have been a cushy gig: the ambassadorship to Germany. But Cox turned down the job. Germany was unstable and violent — and German Chancellor Adolf Hitler's paramilitary army had started to attack and jail thousands of its own citizens.

Two spheres merge in The Avengers: the Marvel Comics universe and the Whedonverse, fans' name for the nerdy wisecracking existentialist superhero world of writer-director Joss Whedon.

The Whedon cult is smaller but maybe more fervent, inspiring academic conferences on such subjects as free will vs. determinism in Buffy the Vampire Slayer. I find a lot of Whedon's banter self-consciously smart-alecky, but I love how he can spoof his subjects without robbing them of stature.

TV writer and producer Steven Moffat specializes in injecting new life into old, familiar characters and stories. He first worked his magic on the revived edition of Doctor Who, leading to several BAFTA and Hugo Awards for the series.

More recently, he has turned his eye to the world's greatest detective, Sherlock Holmes. As the co-creator of the critically acclaimed BBC series Sherlock, Moffat is responsible for updating Sir Arthur Conan Doyle's famous fictional creation for a modern-day audience.

Julia Louis-Dreyfus will forever be known to millions as Elaine Benes, the character she played for nine seasons on Seinfeld. But she was also an early cast member of Saturday Night Live, and she won the Emmy for Best Comedy Actress while starring in the CBS series The New Adventures of Old Christine, which ran for five seasons after Seinfeld.