Star Trek II: The Wrath Of Khan is not only one of the best Star Trek movies, but also one of the greatest Sci-Fi movies ever made. It deals with issues such as facing mortality, the destructive qualities of vengeance, and the selflessness of true friendship. It also has space ships, laser beams, explosions, and William Shatner screaming “KHAAAAAAAAN!”. What more could a Sci-Fi fan want?

It has been 37 years since the film's original release and it still holds up to this day. Here are 10 things you may not of known about The Wrath Of Khan.

Ricardo Montalbán Had Trouble Getting Back Into Character As Khan

When Ricardo Montalbán agreed to reprise his role of Khan Noonien Singh for the movie, it had been over a decade and a half since he played the character in the Star Trek episode “Space Seed.” During the past five years, Montalbán stared in ABC’s Fantasy Island and was very much in character as Mr. Roarke, a lovable host who makes all his guest's fantasy’s come true, and about as far from the hate fulled Khan as you could get.

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Afraid he was “stuck” in his Roarke persona, It took him three of four viewings of his Original Series performance in order to find the essence of Khan once again. 

William Shatner, DeForest Kelley, George Takei, and James Doohan All Almost Didn’t Return

Four of the famous Enterprise bridge crew almost didn’t come back for one reason or another. With Kelley and Shatner, it was script issues; Kelley didn’t care for an earlier draft and Shatner wasn’t sure about playing an older Kirk, even though the character was the same age as the TJ Hooper star (you can determine this via the stardates of Wrath Of Khan and Kirk’s birth in the 2009 Star Trek reboot).

George Takei was also reluctant to return, perhaps due to unfulfilled promises of Sulu having a bigger role or his long-standing feud with Shatner. Apparently, it took a phone call from Shatner in order to convince him to reprise his character.

As for poor old Scotty, it wasn’t that James Doohan wouldn’t play the part, but he couldn’t after suffering a small heart attack. Thankfully, he pulled through and the original crew of the NCC-1701 was united again.

The Battle Of The Mutara Nebula Was Inspired By Submarine War Movies

The Enterprise's battle with the U.S.S Reliant is one of the most iconic space battles in cinema history, taking it’s time to build like a game of chess with both ships playing hide and seek thanks to the disruptive clouds of the Mutara Nebula.

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The epic game of wits It was inspired by old submarine war movies, with director Nicholas Meyer citing 1957s The Enemy Below having the most influence on the tension and pacing.

Kim Cattrall Was Originally Cast As Lt. Saavik

Sex And The City star Kim Cattrall was originally considered for the part of Lt. Saavik in the Wrath Of Khan, but sadly had to pull out due to other commitments.

The role eventually went to Kirstie Alley. Cattrall auditioned for other Star Trek movies before eventually being cast in Star Trek VI: The Undiscovered Country, ironically because Kirstie Ally and Robin Curtis (who took over the role from Ally in Star Trek III, IV, and The Next Generation series) were unavailable.

Cattrall did not accept the role at first, not wanting to be the third actress to play Saavik, but when she learned that the Vulcan officer role was a new character named Valeris, she jumped at the opportunity. 

Kirstie Alley Was A Life Long Star Trek Fan Before Being Cast

What was Kim Cattrall’s loss became Kirstie Alley’s gain. A life long Star Trek fan, as a little girl Alley used to fantasize about being Spock’s daughter.

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It was this fangirl devotion that helped land her the role, as during her audition she mimicked the movements and portrayal of Leonard Nimoy’s famous Vulcan science officer down to a tee. Alley also reportedly refused to take off her make up after shooting, going to bed at night still wearing her Vulcan ears!

Khans Crew Were Made Up Of Chippendale Dancers

Khan is the leader of a crew of genetically enhanced superhumans, and as such, they had to look reasonably buff! Contrary to popular believe Khan’s muscular chest was not prosthetics, but Montalbán’s real pecs that he owed to “countless push-ups.”

As for his men, where in 1980s America do you go to get a gang of beefy guys? Why, The Chippendale striptease dance troop, of course!

While we don’t see Khan's people in 2012s Star Trek Into Darkness, it’s nice to think that lying dormant inside those torpedo containers could perhaps be the cast of Magic Mike!

Chekov And Khan Never Actually Met Before

Whilst exploring the derelict wastelands of Ceti Alpha V, Chekov is the first member of the Enterprise crew that Khan recognizes, telling him that he “never forgets a face.”

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The thing is, Khan has never actually met Chekov before, as the episode “Space Seed” screened in February 1967, a full seven months before Chekov’s debut episode “Amok Time.”

Since then, continuity purists have decided that for the sake of cannon Chekov may have been a part of the Enterprise crew at the time before he was fully instated as a bridge officer.

It Was The First Film To Have A Fully CGI Rendered Sequence

Originally a doomsday device in early scripts, the machine that Khan wants to get his hands on was rewritten as the terraforming “Geneses Device” in order to keep in line with the film's themes of rebirth.

A video that explains what the device does to the crew was originally going to be done in traditional animation, but as the filmmakers wanted something more special it ended up being created by cutting edge computer-generated effects, making it the first fully CGI sequence in movie history. 

Wrath Of Khan Was The Fourth Title For The Film

The original name for Wrath Of Khan was simple: Star Trek II. Then thinking that it needed a bit of oomph they added a subtitle “The Undiscovered Country” (a title that would eventually be used for Star Trek VI).

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Finally, the studio settled on Revenge Of Khan. However, as the third Star Wars film was at the time going to go under the moniker Revenge Of The Jedi, Paramount elected to change Revenge to Wrath in order to separate the two franchises.

Kirk And Khan Were Originally Going To Have A Face-Off

One of the subtle but brilliant things about Wrath Of Khan is that Kirk and Khan never actually share a scene together, communicating to one another via radio and on viewscreens.

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This was not always the case. Apparently in early drafts of the script Kirk and Khan had a 12-minute face to face confrontation. Another draft went full "Star Wars” and had the two battle each other in a sword fight!

Thankfully, the writers restrained themselves and made Kirk and Khan's battle one of wits over brawn, allowing Star Trek to cement itself as the thinking man’s Sci-Fi and giving it enough success for the franchise to continue to this very day.