Transporter Accidents

Still of Riker meeting Riker from The Next Generation's "Second Chances." Photo Credit: Paramount.

Alien Diseases

Still of George Takei as Sulu and Nichelle Nichols as Uhura from "The Naked Time." Photo Credit: Paramount.

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The Star Trek universe has diseases that make the Spanish Flu seem like the common cold. Alien afflictions encountered throughout the show have made crewmembers lose inhibitions and reveal their innermost feelings (as happens in The Original Series episode "The Naked Time," pictured above, in which an infected Sulu pursues his passion for fencing). RELATED: Read the True Story Behind One of the Best Star Trek Episodes Ever In The Next Generation episode "The Naked Now," the Enterprise crew also contract the same illness. A virus in The Next Generation episode "Genesis" makes the crew move backwards on the evolutionary scale, and The Animated Series' "Albatross" focuses on a plague that turns skin every color of the rainbow. Some diseases in the Star Trek universe can even attack ships, as happens in the Voyager episode "The Disease."

Computer Malfunctions

Still from "The Ultimate Computer." Photo Credit: Paramount.

Starships rely on computers for essential functions like air and water recycling, or food processing. But what happens when a super-intelligent computer gets a virus that even McAfee wouldn't be able to scrub out (The Next Generation episode "Contagion")? RELATED: 10 Exceptional David Gerrold Books Or if the computer wants to run its own version of the 1980s movie WarGames (The Original Series' "The Ultimate Computer")? Computers are an invaluable tool in space—but they often have unexpected side effects.

Time Travel Mishaps

Still of Joan Collins and William Shatner from "The City on the Edge of Forever." Photo Credit: Paramount

Time travel is a staple of the Star Trek universe, but it often comes with complications. For example, in The Original Series' "The City on the Edge of Forever," Dr. McCoy sets off a chain of events that causes Hitler to win World War II. Thankfully, Kirk and Spock can also use time travel to fix McCoy's impact on the past—but not without significant loss. In the Deep Space Nine episode "Past Tense," members of the Defiant crew accidentally arrive on Earth in the year 2024, and have to face the dangers of a dystopian America “Made Great Again," in which the unemployed and mentally ill are segregated in so-called "Sanctuary Districts." RELATED: 8 Times Star Trek Accurately Predicted Future Technology

Holodeck/Holosuite Hijinks

Still from Voyager's "Heroes and Demons." Photo Credit: Paramount

Do you ever wish your computer could create anything you ever wanted? Welcome to the Holodeck, a holograph simulator that allows you to go anywhere, be anyone, and do anything. Don't worry, it comes with safety devices that prevent serious injury or certain death—unless your evil holo-nemesis gets loose on the ship (The Next Generation: "Ship in a Bottle"). Or unless you need to kill off your infected crewmates with a holographic machine gun (as happens in First Contact). Or unless it's taken over by “photonic life forms” with a love for medieval LARPing–and really sharp swords (Voyager: "Heroes and Demons").

Alien Plants

Still of the Enterprise crew and Leila Kalomi in "This Side of Paradise." Photo Credit: Paramount

The galaxy is full of hostile aliens, such as the Klingons, the Romulans, the Cardassians, and Species 8472. But it's also full of hostile alien fauna. A trip through the final frontier might see you sampling some hallucinogenic spores, as Spock and the rest of the Enterprise crew do in The Original Series' "This Side of Paradise." RELATED: 10 Menacing Characters from Sci-Fi That We Never Want to Meet Or, you might face flowers that shoot deadly poison darts like those found in The Original Series episode "The Apple" on planet Gamma Trianguli VI, or thorns that inject a virus which feeds on erotic dreams (The Next Generation's notoriously terrible episode "Shades of Gray").

Warp Drive

Still from "The Force of Nature" of Data standing in front of a map of the Hekaras Corridor, a region destabilized by repeated exposure to warp fields. Photo Credit: Paramount