Broadcast of a murder mystery film starring Loni Anderson,^[3] titled Without Warning, is interrupted with a news bulletin of a series of three earthquakes, one of them located in the Thunder Basin National Grassland area of Wyoming.^[4] The film resumes but a few moments later is interrupted for good as coverage, led by Sander Vanocur and Dr. Caroline Jaffe, begins of a Halloween night meteor impact on the United States. Additional impacts are reported in southern France and a remote area of China. Lone survivors are found at the Wyoming and France impact sites, a girl and a young man, respectively. The girl had been reported missing from a city hundreds of miles away from the impact. Both survivors are badly burned and their speech is unintelligible.

The three impact sites begin broadcasting an ear-piercing radio signal that cripples aircraft flying within latitudes immediately surrounding the impacts. Another larger object is detected moving towards the North Pole. The United States, despite protests from world leaders and scientists, orders several aircraft to intercept the object before it impacts with the earth and destroy it using nuclear weapons. The destruction of the larger object is successful, though the attacking aircraft are brought down by another radio signal broadcast by the object shortly before its destruction.

A scientist, named Dr. Avram Mandel, who has been studying the impacts, is flown by an F-16 to NASA's Johnson Space Center in Houston, where reporters are being briefed on the latest incident. He reveals that his determination is that the impacts were in fact an attempt at first contact by an alien species and that, by destroying the follow-up vehicle, Earth has declared war. Other mysteries occur. At one point, the population of the town of Faith, Wyoming, home to a devoutly religious community, vanishes without a trace.

Dr. Mandel's fears are confirmed when he later reveals that three more objects, each two miles wide, will soon impact Washington, D.C., Moscow, and Beijing - the capital cities of the only three nations capable of first-strike nuclear warfare. The survivors of the initial impacts are identified as Jean-Paul Chounard and Kimberly Hastings. They succumb to their wounds and die. Nuclear weapons are launched to intercept the three incoming objects, which are successfully destroyed. Scientists finally decipher Chounard and Hastings' speech. They are each speaking a fragment of a message. When combined, the message appears to be a recital of the message from the U.N. Secretary General that had been included on a special recording housed aboard Voyager 2.

Moments later, NASA detects hundreds more asteroids, all heading towards Earth. As a stunned Vanocur and Jaffe react to reports of cities and entire countries being destroyed worldwide, Vanocur solemnly quotes from William Shakespeare; "The fault, dear Brutus, lies not in our stars, but in ourselves" as a rumble is heard and the picture cuts to static.

• Sander Vanocur as Himself
• Jane Kaczmarek as Dr. Caroline Jaffe
• Bree Walker as Herself
• Dwier Brown as Matt Jensen
• Brian McNamara as Mike Curtis
• James Morrison as Paul Whitaker
• Ashley Peldon as Kimberly Hastings
• James Handy as Dr. Norbert Hazelton
• Kario Salem as Dr. Avram Mandel
• Spencer Garrett as Paul Collingwood
• Gina Hecht as Barbara Shiller
• John de Lancie as Barry Steinbrenner
• Patty Toy as Denise Wong
• Dennis Lipscomb as Dr. Robert Pearlman
• Ron Canada as Terrence Freeman
• Victor Wilson as Mark Manetti
• John M. Jackson as Dale Powell
• Ernie Anastos as Himself
• Phillip Baker Hall as Dr. Kurt Lowden
• Jim Pirri as Robert Marino
• Alan Scarfe as General Lucian Alexander
• Cynthia Allison as Herself
• Arthur C. Clarke as Himself
• Sandy Hill as Herself
• Michelle Holden as Herself
• Mario Machado as Himself
• Warren Olney as Himself
• Saida Pagan as Herself
• Richard Saxton as Himself
• Debra Snell as Herself

Co-starring edit

• Randy Crowder as Deputy Anson Peters
• Frank Bruynbroek as Jean-Paul Chounard
• Diana Frank as Sylvie Chounard
• Marnie McPhail as Donna Hastings
• Sherri Paysinger as Pamela Barnes
• Robert Peters as Dwayne Haskell
• Lou Beatty Jr. as Dr. Jonas Tremblay
• John DeMita as Major Powers
• Tyler Cole Malinger as Tyler O'Neal
• Marnie Mosiman as Annie O'Neal
• Armand Schultz as David Case

The film employed "accelerated time" (i.e. events said to have taken place an hour apart actually take place a few minutes apart), among other storytelling devices to make it clear to viewers paying attention that it was not real; including the mention of the year's G7 Summit, which had already come and gone three months before the film released. This, combined with the casting of Jane Kaczmarek, a recognizable actress, as well as several other well-known performers in secondary roles (Star Trek: The Next Generation guest star John de Lancie as a reporter and Philip Baker Hall as one of the doctors in the space station), was expected to alleviate any concerns that the story being shown was actually happening. Ron Canada, who appeared in the film as a science author being interviewed by Sander Vanocur, had previously worked as a television news reporter for stations in Baltimore and Washington, D.C. during the 1970s before becoming an actor. However, the casting of noted (albeit retired) news anchor Vanocur and noted journalist Bree Walker (who had previously anchored for Los Angeles CBS O&O station KCBS-TV) in major roles portraying themselves, plus a faux interview with noted author Arthur C. Clarke, still left some viewers wondering.

During the film's broadcast, CBS had warnings during the commercial breaks stating that the film was completely fictional,^[5] and that the events were not actually happening. Some CBS affiliates, such as KHOU in Houston, had similar warnings in the form of a news ticker "crawl" during the broadcast. The producers used actual CBS News graphics to help accentuate the feeling that it was real (though they used a different network logo, a sphere within an outline of a TV screen), however, leading to at least one uproar over the events. In Fort Smith, Arkansas, the CBS affiliate (KFSM-TV) reported that they had received dozens of calls regarding the incident and whether it was actually happening. The area's ABC, Fox, and NBC affiliates (respectively KHBS, KPBI and KPOM-TV) were also flooded with complaints, asking them why they were not covering this event at the same time that CBS was covering it. In several other markets, including Detroit, Michigan, and San Diego, California, the local CBS affiliates (respectively, WJBK, which would switch to Fox six weeks later, and KFMB-TV) refused to air this TV movie.

Some accused CBS of being irresponsible in showing the movie during the primetime hours, when some children were still out trick-or-treating (even though the movie actually aired the night before Halloween). Indeed, the film explicitly takes place on Oct. 31, with trick or treaters featured in several news reports within, but very few occasions have happened since Orson Welles' 1938 The War of the Worlds radio broadcast (which also aired on October 30) that so many people have been taken in by a production such as Without Warning. The film borrowed one of the locations from Welles' broadcast. Welles used the village of Grover's Mill, New Jersey, as the first landing site of the Martians in his tale. Without Warning uses the fictional town of Grover's Mill, Wyoming, as a homage to Welles' broadcast, and the original broadcast was preceded by a brief prologue referencing the War of the Worlds broadcast, with the narrator reiterating that the film about to be shown was fiction and presented in the same spirit.

The film was released on DVD on July 8, 2003, nearly nine years after its initial, and only, showing on CBS. However, it has since been shown outside the United States, such as the United Kingdom where it aired on Sci-Fi, minus the commercial break warnings.^{[citation needed]}

• The War of the Worlds radio drama (1938)
• Special Bulletin (1983)
• Ghostwatch (1992)

• Without Warning at IMDb