Debut: January 10, 1967, Tuesday, 8:30 PM EST, ABC
Last Network Run Episode: September 17, 1968,  Tuesday, 10:00 PM EST, ABC

The Invaders centred on David Vincent (Roy Thinnes), a man who had learned that aliens are plotting to take over the world.  Because of this he became a fugitive, moving from place to place lest the "invaders" catch him.  The aliens had already infiltrated human society to a large degree.  There were aliens in local police departments, the news media, the corporate world, even the government.  Anyone could be an invader from outer space. Luckily their ability to take human form was somewhat flawed. As they had no hearts, they would have neither a pulse nor a heartbeat. Sometimes their form might be slightly imperfect, most often the pinkie finger would jut out awkwardly. Finally, their bodies would glow when in need of the regeneration required to keep their human shape.  When an Invader was destroyed, his body went up on a cloud of red smoke, with nothing but ashes left behind.

The Invaders was one of the earliest shows produced by Quinn Martin's Q-M Productions (previously he had supervised The Untouchables).  Its line producer was Alan Archer. The series was created by Larry Cohen, the director of the Seventies cult classic lt's Alive. Its  inspiration perhaps came not from the Sixties so much as it did the Fifties.  The concept behind The Invaders is reminiscent of  Invasion of the Body Snatchers and any number of other alien invasion movies. in which aliens take human form in order to take over the world.  At the same time, however, the series could well have drawn upon fears common during the Red Scare of the early Fifties for inspiration. The Invaders  is in some ways reminiscent of the Fifties syndicated series I Lead Three Lives.  In that series it was put forth that the Communists had either recruited or planted various individuals throughout American society--a premise similar to The Invaders. Indeed, in explaining the premise of  The Invaders, producer Archer said, "The new neighbours across the street.  The substitute teacher.  That too-pretty secretary in your husband's office.  Any one of them might be an invader from outer space.' Replace 'invader from outer space' with 'Communist' and you have the central premise of I Led Three Lives.

The Invaders debuted as a mid season replacement January 10, 1967, Tuesday night at 8:30 EST.  The Invaders' first season established it as a solid adventure series, albeit one whose plots generally fell into one of three broad categories.  The first category of plots involved Vincent offering assistance to those somehow threatened by The Invaders .  In "The Experiment" Vincent stopped an assassination attempt upon a scientist who has evidence of a spaceship landing. In "The Leeches"  Vincent helped an electronics expert who fears the invaders plan to abduct him.  A second category of plots involved the invaders' efforts to silence Vincent. In "'Well of Crystal' the invaders abducted his brother and his pregnant wife.  In "The Condemned' they framed him for murder.  A third category of plots involved Vincent's efforts to get solid evidence of the invaders' presence on Earth.  In "The Betrayal" Vincent discovered a strange computer tape that could proof of the invaders' plans.  In "Genesis" Vincent discovered an undersea lab.  Finally, a few episodes fell into none of these categories.  In "Nightmare" Vincent investigated the attacks of carnivorous insects in a small town and their link to the invaders. In  "Panic" Vincent and the invaders raced to capture wounded alien.

Over all, The Invaders' first season was a fairly good one.  The scripts, from such writers as Anthony Spinner and John Kneubahl, were fairly strong.  The series' direction, provided by such men as Joe Sargent, Paul Wendikos, and John Meredyth Lucas, was superior to that of most TV series.  The Invaders' only drawback was that its plots were generally one of three types and most. every episode followed a definite formula.  People Vincent trusted often turned out to be aliens. while those who weren't aliens believed he was a crank.  This lent an air of predictability to an otherwise strong series.  Regardless, The Invaders' ratings rose from January 1967 to September, 1967, when they were somewhat respectable.

The Invaders' second season proved to be better than Its first with more variation in the plots of episodes (although most people still thought Vincent was crazy).  Midway through the second season, in an episode titled "The Believers" Vincent linked up with a group headed by Edgar Scoville (Kent Smith) who also knew of the invaders' existence. From this episode on The Believers assisted Vincent with money, business, and political connections.

On the whole, the second season produced better scripts than the first.  In "The Prophet" Vincent had to stop an invader who subverted humans by masquerading as an evangelist. In the two-part "Summit Meeting," Vincent thwarted a plot by the invaders to kill world leaders (apparently they got the idea from THRUSH).  In Jerry Sohl's "Dark Outpost," Vincent investigated the invaders' susceptibility to human disease and wound up aboard an alien spacecraft.. In "'The  Vise' Vincent faced the thankless task of proving an apparently African American government appointee to be an invader.  In "The Captive," an invader posing as a Communist delegate captured in the United Nations threatened to start World War III. Despite the greater variety of plots during the second season, the formula in which no one ever believed Vincent (and later his Believers as well) except the invaders remained firmly entrenched as part of the series.

Although its second season was better than its first, The Invaders slid in the ratings following its peak in September. In January the series was moved to a new time slot on Tuesday night, 10:00 EST. There is fared no better and its ratings failed to improve. The Invaders left the air September 17, 1968.

The failure of The Invaders was due in a large part to its time slot.  For most of its run The Invaders faced the indomitable Red Skelton Hour on CBS.  Its move to 10:00 EST Tuesday night hardly helped matters.  The series faced the last half of NBC's Tuesday Night at the Movies.  Against such competition, the series was probably doomed.

There were perhaps other factors in The Invaders' failure to capture the audience as well. In nearly every episode almost no one ever believed Vincent.  When someone did believe him, they usually turned out to be an alien.  This made the series rather predictable to a degree, and undermined Vincent's credibility-if no one on the show believed him, why should the viewer?  This formula, in which no one ever believes Vincent, may then have driven viewers away with its utter predictability.

A more important reason for the series' failure to maintain an audience may be that The Invaders simply debuted in the wrong decade.  Despite the often bleak headlines about racial riots, the Vietnam  War, nuclear escalation, and the Cold War, the Sixties were for the most part an optimistic time.  There was for many a feeling in the air that all of man's problems could be solved if all of us would just take action. "Love" was the buzz word of the day. The Invaders expected the viewer to believe that there was an enormous conspiracy which had placed alien invaders in every institution of human society. Furthermore, fighting the invaders was a nearly hopeless proposition. The invaders had vast resources at their command and your fellow human beings would think you were nuts any time you mentioned them. The Invaders was a very pessimistic series in some respects.  It was perhaps better suited to the Fifties, when Americans were eager to believe that 'Communists' had infiltrated every part of our society, or the Nineties, when trust in the government has largely broken down.  In the Sixties, however, people probably preferred to watch Batman, where the villains were still outside our governmental and social institutions, or one of the many spy shows, where they knew our side would win.

Despite The Invaders' short run,  it has remained one of the best remembered adventure series of the Sixties. In fact, it had enough of a following to warrant a two part telefilm based on the series to air in 1995 on the Fox network. This movie featured Scott Bacula as Nolan Wood, a man who was manipulated by the invaders through an implant, but who  broke free of their control (he was autistic, hence his brain patterns made him difficult to manipulate. Roy Thinnes only had a cameo in the film as David Vincent, who provides Nolan with information from his twenty odd years of fighting the aliens. Despite the near absence of Vincent, the telefilm did manage to capture some of the flavour of the original series, and even expanded upon the mythos surrounding the aliens (for instance, they breath carbon monoxide).

The reason The Invaders is so well remembered is perhaps because it was so different for its time. Most science fiction series, from Voyage to the Bottom of the Sea to Star Trek, possessed a good deal of optimism. Man would not only survive, he would prevail. On The Invaders whether man would survive, let alone prevail, rested on the shoulders of only one man and later a small group of individuals. As sated earlier, The Invaders was not an optimistic series. Too, it must be pointed out that prior to The Invaders no other series had ever dealt with the concept of alien invasion, event though the idea had been around for ages. The Invaders can then be considered a bit of a breakthrough series. It can be justifiably seen as the predecessor of V, War of the Worlds, Dark Skies, Earth: the Final Conflict, and even The X-Files. While its run may have been brief, then, The Invaders appears to have had a lasting influence on American pop culture.