''In Search Of...'' is a syndicated documentary television series that was broadcast weekly from 1977 to 1982, devoted to mysteries and phenomena. It was created after three successful one-hour TV documentaries, ''In Search of Ancient Astronauts'' in 1973 (based on the book ''Chariots of the Gods?'' by Erich von Däniken), and ''In Search of Ancient Mysteries'' and ''The Outer Space Connection'' (both of which were written into popular paperbacks by series-creator Alan Landsburg) in 1975. All three feature narration by Creator/RodSerling, who was the initial choice to host the series. After the death of Serling, Creator/LeonardNimoy was chosen to be the host of the spin-off series.

The series conducted investigations into the controversial and paranormal (e.g., [=UFOs=], Bigfoot, and the Loch Ness Monster). Additionally, it featured episodes about mysterious historical events and personalities such as Anna Anderson/Grand Duchess Anastasia, the Lincoln Assassination, the Jack the Ripper murders, infamous cults (e.g. Jim Jones), and missing persons, cities, and ships (e.g., UsefulNotes/AmeliaEarhart, Jimmy Hoffa, D. B. Cooper, the Mary Celeste, the Titanic, the lost Roanoke Colony). Because the show often presented offbeat subjects and controversial theories, each episode's opening credits include a verbal disclaimer about the potentially conjecturable nature of the evidence and theories to be presented:

-->This series presents information based in part on theory and [[WildMassGuessing conjecture]]. The producer's purpose is to suggest some possible explanations, but not necessarily the only ones, to the mysteries we will examine.

Compare and contrast with the various series hosted by Arthur C. Clarke (''Mysterious World, World of Strange Powers, Mysterious Universe'') that covered many of the same topics but did so in a more scientific manner, usually debunking the various theories or providing scientific explanations for phenomena instead of holding up any and all random explanations as equally valid, legitimate answers.

Not to be confused with ''[[Film/StarTrekIIITheSearchForSpock The Search For Spock]]''.

!!This show provides examples of:

%%* AlienAbduction
* AncientAstronauts: At least one episode is devoted to the subject, while other episodes on ancient wonders like the Pyramids, the Nazca lines, etc pose the question of outside "help".
%%* BigfootSasquatchAndYeti
* CapturedByCannibals: Discussed in the episode "Michael Rockefeller".
* DatedHistory: Quite a few of the mysteries aren't so mysterious anymore.
** For instance, they had an article about Carlos as "The Most Wanted Man in the World." In 1994, the Sudanese government was convinced to give him up and he was arrested in 1994 and now is serving a life sentence in prison.
** Likewise, they did a story on UsefulNotes/JosefMengele. He died in 1979 and his grave was found in 1985. Now that Mengele's identity while living in South American is known, the dramatic tales of Mengele's narrow escapes from {{Nazi Hunter}}s related in the episode have turned out to be bogus.
** Other subjects covered like astrology, dowsing, communicating with the dead, the predictions of Nostradamus, etc have been thoroughly discredited as utter nonsense by modern scientific skeptics.
** A 1981 episode was about the search for the ''Titanic''. The wreck was found just four years later. Of course, the episode repeats as truth the then-current theory that the ''Titanic'' sank in one piece, which was disproved when the wreck was found in two pieces. (Hence the reason pre-1985 ''Titanic'' films portray it sinking in one piece.)
** An episode covers the real account of ''Literature/TheAmityvilleHorror'', which has now been debunked as a [[BasedOnAGreatBigLie hoax]].
** Noah's Ark and the great flood is explored. Noah's flood being a myth has been the consensus of the geological community since the late Victorian era, so technically history had already marched on when the show was made. The episode acknowledges this and challenges the "nineteenth-century scientists" who disbelieved in the flood with the "twentieth-century scientists" who do. One of the "twentieth-century scientists" interviewed for this show is [[http://en.wikipedia.org/wiki/Henry_M._Morris this guy]].
** There's an episode about Anastasia Romanova, including an interview with an ancient-but-still-living Anna Anderson. In 1991, DNA evidence proved Anna Anderson was not Anastasia. Furthermore, Anastasia's body was found in 2007, proving she was killed along with the rest of her family. As a side note, the episode is clearly an artifact from a time when [[UsefulNotes/ColdWar certain issues]] prevented Western historians from having direct access to Russia. Come to think of it, that probably played a large part in how that legend survived so long.
%%* {{Dracula}}
%%* EenieMeenieMinyMoai
* InsaneTrollLogic: And it doesn't just come from the crackpots interviewed on the show; the [[Creator/LeonardNimoy narrator]] uses it in spades. Almost every other sentence he utters consists of "Could this mystery be explained by ghosts/magic/aliens/telepathy?"
** At one point he asks how ancient native Americans could draw pictures of elephants since they couldn't know what an elephant was, conveniently leaving out the fact that frigging MAMMOTHS lived alongside humans in the Americas until 10,000 years ago, which was common knowledge even at the time of the series.
* LandmarkOfLore: And there are many!
** The Pyramids
** Stonehenge
** The Bermuda Triangle
** Nazca, Peru
** Easter Island
** The Great Wall of China
* Creator/LeonardNimoy: The narrator.
* {{Mundanger}}: In addition to the standard episodes about the supernatural and extraterrestrial, every season had at least one episode about unambiguously real natural disasters, like earthquakes, tornadoes, and volcanic eruptions, and the "mystery" of predicting and mitigating their effects. (Although the "Earthquakes" episode did include the debunked theory that planetary alignments can produce earthquakes.)
* NaziGold: The episode "Nazi Plunder".
* PirateBooty: The Oak Island treasure pit mystery.
%%* PsychicPowers
%%* PyramidPower
%%* SpookyPhotographs
* TheSeventies: While it technically continued into the early '80s, this is a '70s show through and through.
* ShoutOut: When the subtitle of the third StarTrek movie was announced, many viewers and reviewers noticed the similarity between it and this series.
* StockUnsolvedMysteries: While not a work of fiction, the show presents well known mysteries and then offers practically [[WildMassGuessing every single wild theory]] under the sun as a possible explanation for them.
* TalkingHeads: Every episode has a significant chunk of time devoted to interviews with eyewitnesses and "experts" using this format.
%%* TimeTravel
%%* TheTunguskaEvent
* WhoShotJFK: The KGB, and the FBI covered it up because they didn't want to admit the Soviets outsmarted them. The show also alleges that "Oswald" was actually a Soviet lookalike.
* WildMassGuessing: All over the place, to the point where the show has an opening disclaimer about it.