Currently, a lot of information is presented to us, to believe or not to believe. With so much talk about alternative truths and , it is more important than ever to decipher what is real and what is imaginary.

Movies provide a rich and engaging form of entertainment and , as story-telling can also make people more aware of current and past events. Research has shown that people learn very effectively from stories and narratives, engaging our brain in ways that are both pleasurable and incredibly complex [1, 2], so movies (and not just documentary form) are often ways for people to learn about the past. Our imagination is ready for action, and movies can provide a tantalizing twist, often portraying World Wars, the , slavery, the Holocaust, or space exploration. Actors can become incorporated into people’s imagery of the past, such as in Mel Gibson's The Passion of the Christ (2004) starring Jim Caviezel as Jesus, and Daniel Day-Lewis as Abraham Lincoln in Lincoln (2012).

The question is, to what degree can misinformation, or slight variations on what actually happened in the past, blend into people’s minds while watching movies? Does this sometimes less-than-accurate perspective then become embedded in , and with time, become a new version of the truth? This might be especially so for a younger generation, who do not personally remember the more remote past or did not live through the historical events in question.

As an example, Quentin Tarantino’s Once Upon a Time in Hollywood provides an engaging story and background for the 1969 events that led to the Sharon Tate Manson-clan murder spree. Living up to its story-book title ("Once Upon A Time...") (spoiler alert) the movie provides a much different ending, as Sharon Tate never meets her demise in this tale. Most people over the age of 60 know about the Manson-family murders and Sharon Tate.

The movie provides a much less horrific ending for Tate and an alternative tale—complete with Tarantino-style violence (it involves a flame thrower) and using instead of historical facts. The Manson clan has the tables turned on them. However, in what is a deviation from the truth of what happened 50 years ago, it becomes possible that people (especially young adults) will now know a different version of reality—and may not question the movie’s twist on truth, and end up believing some of the fictitious events in the movie.

Research has shown that presenting people with misinformation—some information or event that is inconsistent with the truth of what happened earlier but is highly believable, can lead to not only some initial confusion, but it can then alter memory [3]. As a result of introducing misinformation in a psychology experiment on the exact topic, people will claim to have been lost in a mall as a child after being told this story had happened to them, or that as a child they met Bugs Bunny at Disneyland to refresh your memory, Bugs is a Warner Bros. character and thus couldn’t be seen at Disneyland) [4].

People are prone to believe stories and what makes sense often without questioning the events that are being suggested. Movies might provide just the right amount of entertaining and (sometimes subtle) misinformation that can lead to memories and history being altered in the process.

Movies provide us with entertainment and fodder for our imagination. They also reference history and make people think about what happened in the past, and what could happen in the future (such as the memorable Back to the Future trilogy). Presenting tales and alternative ending in the context of a real event can make people think what could have happened if only a few things were different—but these variations on the truth can also lead to some implanted memories for people who only have a vague understanding of the past.

In the context of and social psychology, the “sleeper” effect can lead people to believe something that they earlier didn’t believe or agree with, if they then experienced some reference to it and after some time they are even more likely to believe it [5]. Sleeper effects can make people believe things even if initially we are not likely to believe it.

Quentin Tarantino is not intentionally trying to dupe people into thinking things were different 50 years ago, instead he is allowing us to imagine how things could have been different if a few small or seemingly random events happened or different choices were made by certain characters. He took creative license to shed a brighter light (flame-thrower style) on a dark event. Movies can allow the mind to imagine, and it is then up to us to differentiate what we imagine with what actually happened in the past, but sleeper effects can make us reimagine the past in ways that can have profound effects on our later memory, which can be modified each time we visit events from the past [6]. Students may also misremember historical events based on the movies that they were exposed to in classroom learning settings [7], suggesting that Hollywood can alter younger peoples' perception of past historical events.

Ideally, movies that provide variations of the past will make people research what actually happened, to have a more complete understanding of the events, but it can also lead to some subtle changes in history from the younger viewers’ point of view.