WEST WINDSOR — Bob Sanders was in Grovers Mill when Martians invaded the Jersey town — 75 years ago today.

"William Dock saw the water tower in the moonlight, thought it was a spacecraft," recalls Sanders, now 81 and a lifelong resident of the West Windsor hamlet. "He took a couple shots at it with his double-barreled shotgun."

The town was in a tizzy. The nation was in a panic. Murderous Martians had invaded Earth, their unlikely first landfall Grovers Mill, outside Princeton.

"We sat down and listened to it on the radio," Sanders says of "The War of the Worlds'' broadcast on Oct. 30, 1938. "Some of the local people put their families in their cars and drove out of town."

Good heavens, something's wriggling out of the shadow like a gray snake. Now it's another one, and another. They look like tentacles to me. There, I can see the thing's body. It's large, large as a bear and it glistens like wet leather. But that face, it ... Ladies and gentlemen, it's indescribable.

It was Halloween eve. A musical break in the popular Chase and Sanborn Hour — with ventriloquist Edgar Bergen and dummy Charlie McCarthy — led radio listeners to do some channel-surfing, radio-style. If they happened upon the Columbia Broadcasting System's "Mercury Theater on the Air" and didn't catch one of several disclaimers, they might well have thought the end of the world was near.

Martians had landed in a town in Central Jersey no one had heard of, killing 7,000 soldiers, then marched through the Watchung Mountains and into the swamps of North Jersey, the broadcast reported. One of their fearsome fighting machines straddled the Pulaski Skyway, shooting death rays at army bombers. The invaders from the red planet would advance upon and destroy New York City, Chicago, St. Louis and other cities.

None of it was true.

Orson Welles, a 23-year-old theater actor/producer and voice of radio soap operas, had pulled off a monumental hoax.

"The War of the Worlds," which Welles would describe as the Mercury Theatre on the Air's "radio version of dressing up in a sheet and jumping out of a bush and saying 'Boo,' " caused nationwide confusion, panic and hysteria.

"Specific local New Jersey names recurred throughout — this was a rarity — and provided chilling reality," says Rich Phoenix, president of the New Jersey Radio Museum. "Even if the audience was unfamiliar with Grovers Mill, talk of Newark, Plainfield, the Watchung Mountains, familiar highway names and many more specifics helped ram home the entire terrifying tale, complete with marauding Martians."

But there were no Martians, no death-rays — and even the subsequent newspaper reports of deaths and suicides among panic-stricken listeners proved false.

Welles, his reputation as an enfant terrible growing (he hired an ambulance, siren wailing, to whisk him from studio to studio in New York for radio gigs), had pulled a night-before-Halloween prank on the nation.

"I would put those minutes of old-time radio up against any murder mystery or thriller ... up against any other piece of motion picture or radio drama that's been created before or since,'' says David Acord, author of "When Mars Attacked,'' an ebook on the broadcast published earlier this year.

What Welles did was brilliantly tap into a considerable national neurosis. America was still clawing its way out of the Great Depression; in 1938, unemployment rose to nearly 20 percent. The Hindenburg had exploded over Lakehurst the year before. There was the grim spectre of Hitler and a world war.

Martians landing in New Jersey was not as far-fetched as it sounded, says Cathleen O'Connell, producer/director of the PBS American Experience show on "The War of the Worlds," which aired last night and can be viewed on pbs.org. Several days before the broadcast, newspapers ran a story about an astronomer predicting life on Mars.

Ladies and gentlemen, I have a grave announcement to make ... The battle which took place tonight at Grovers Mill has ended in one of the most startling defeats ever suffered by any army in modern times. ...

"Welles and his players did a magnificent job of replicating the sound of radio of its times," Phoenix says. "The concept of 'live' radio reporters checking in from remote locations was exploited to a highly sophisticated degree along with fright-instilling sound effects and screaming from the Martians' well-toasted victims."

Why Grovers Mill?

The story goes that Howard Koch, who wrote the "The War of the Worlds" script adapted from the H.G. Wells novel of the same name, pulled into a New Jersey gas station and asked for a state map. Back home, he spread out the map, closed his eyes, and poked it with a pencil. The tip landed on Grovers Mill.

Between four million and six million people listened to the broadcast. About 1.7 million people, according to one study, thought it was a real broadcast, with 70 percent of those stating they were frightened.

This is Newark, New Jersey ... This is Newark, New Jersey ... Warning! Poisonous black smoke pouring in from Jersey marshes. Reaches South Street. Gas masks useless. Urge population to move into open spaces ... automobiles use Routes 7, 23, 24 ... Avoid congested areas. Smoke now spreading over Raymond Boulevard ...

The CBS switchboard quickly flooded with calls from panicky listeners. At the Lido movie theater in Orange, according to Acord, "a man ran into the lobby and shouted that a meteor had crashed into the middle of Raymond Boulevard in Newark'' and poisonous gas was leaking from it.

"I had become so frightened, I began to cry," Josephine O'Cone of Summit wrote in a letter to Welles, which was read on the PBS program. "I immediately ran downstairs and grabbed my mother and a coat and key. I kept coughing and crying. Mother we're going to die tonight. Mother, the black smoke is getting to me — can't you smell it?"

Ingeborg Zimmer of Bloomfield, another of whose letters to Welles were read on the PBS program, grabbed her picture albums.

"I guessed I figured I could show them to St. Peter, like before-and-after pictures, cause I figured when I saw him I might just be a charred piece,'' Zimmer wrote.

I'm speaking from the roof of the Broadcasting Building, New York City. The bells you hear are ringing to warn the people to evacuate the city as the Martians approach ... All communication with Jersey shore closed ten minutes ago. No more defenses. Our army wiped out ... artillery, air force, everything wiped out. This may be the last broadcast. We'll stay here to the end.

A man dashed into a Maryland state police barracks and screamed that "hundreds'' of people were jumping from the Brooklyn Bridge. Inside a New York City grocery store, a teenage girl said a giant meteor had fallen and that "a lot of little men jumped out'' and started killing people.

Word spread soon enough, though, that there were no Martians, no death rays. The New Jersey State Police sent out a teletype: "Note to all receivers. Broadcast as drama re this section being attacked by residents of Mars. Imaginary affair.'' But officials of cities that had been "destroyed'' were not amused. Lawsuits were threatened.

The most colorful comment came from a South Carolina judge named A.G. Kennedy, describing the broadcast as the "consummate act of asininity,'' and Welles as "a carbuncle on the rump of degenerate theatrical performers.''

But "The War of the Worlds" catapulted Welles to stardom. Two years later, he would start work on "Citizen Kane,'' acknowledged as one of the greatest movies ever.

John Houseman, a key member of the Mercury Theatre team, would have a distinguished acting career, although many remember him most for his commercial for Smith Barney ("They make money the old-fashioned way; they earn it'').

Today, a monument in Van Nest Park in West Windsor marks the infamous broadcast. Nearby, Grover's Mill Coffee House and Roastery is a museum to all things Martian, with front-page newspapers, paintings, movie posters, and other memorabilia.

"We're kind of the keepers of the flame," co-owner Franc Gambatese says of his collection, much of it donated.

Tonight, a live broadcast from the coffee house marking the broadcast's 75th anniversary will run from 7 p.m.-midnight on radiononcemore.com. Also, a live performance of "The War of the Worlds" will be held 8 p.m. Nov. 2 at the Hamilton Stage for the Performing Arts in Rahway.

"Welles did a great job at making this sound believable,'' says Gambatese, who did his senior thesis on the broadcast. "It was the '30s. You couldn't turn on CNN and find out what was going on."

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