Like Stephen King, Robert Ludlum, and Ian Fleming, Tom Clancy was one of the few authors who were fortunate enough to have most of their books adapted into feature films. Clancy, who died in 2013, was known for his espionage and military science novels. President Ronald Reagan even confessed to being a fan of his work.

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Clancy's most popular fictional character Jack Ryan has been portrayed by a number of actors in different films. Currently, there's a brilliant Amazon series about the CIA agent too. However, the adaptations, though successful,  haven't always been faithful to Clancy's work. This made the author clash with producers frequently when he was alive. Here are the major ways the movies deviate from the books.

Jack Ryan Hacking Into Ritter's Computer To Steal Files

Harrison Ford as Jack Ryan holding a piece of wood in Clear and Present Danger

In the novel Clear And Present Danger, Jack Ryan manages to break into CIA Director Of Operations Robbert Ritter's safe to get access to documents that prove the existence of "Operation Reciprocity." In the movie starring Harrison Ford in what is actually one of his most badass roles, this scene is switched up a bit. Instead of the safe, Ryan manages to hack into Ritter's computer and tries to locate the files. The slight change is definitely made to align with modern files.

However, Tom Clancy wasn't too pleased with some of the changes. In an interview, he lamented: "Clear and Present Danger was the No. 1 best-selling novel of the 1980s. One might conclude that the novel’s basic storyline had some quality to it. Why, then, has nearly every aspect of the book been tossed away?"

Felix Cortez Killing Moira

Also, in the Clear And Present Danger, Colombian drug Lord Felix Cortez doesn't kill Moira, the secretary to the FBI director after seducing her. When he learns that FBI director Emil Jacobs will make the trip to Colombia, he keeps her alive. She attempts suicide after learning that she was being used but she survives.

Later on, Deputy Assistant to the FBI Dan Murray goes with her to Guantanamo Bay where Cortez is being held in order to help her put the trauma behind her. However, in the movie, Cortez kills Moira as soon as he learns that the FBI director is coming to Colombia.

Ryan Saves The Prince And Princess Of Wales

Harrison Ford as Jack Ryan holding a gun in Patriot Games

In Tom Clancy's 1987 novel Patriot Games, Jack Ryan saves the Prince and Princess of Wales as well as their new baby from being kidnapped by the Irish terrorist group Ulster Liberation Army. The prince, princess and their son are based on Prince Charles, Princess Diana, and Prince Harry.

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However, in the movie that also starred Harrison Ford, the super CIA agent saves a fictional British leader knows as Lord William Holmes and his wife. Perhaps the change was made to avoid diplomatic problems. Tom Clancy still wasn't impressed. Despite positive reviews from critics, he disowned the movie.

Sean Miller's Revenge

Sean Bean looking menacing in Patriot Games

Also in Patriot Games, the book sees Sean Miller targeting Ryan after he saves the Prince and Princess. Sean is also bitter because he ends up in jail. So, he plans to go after Ryan in America. He also wants the attack on Ryan to be blamed on the Provisional Irish Republican Army so that the American government can stop ing them.

However, in the movie, Miller (Sean Bean) wants revenge because Ryan killed his brother. As is the norm, Sean Bean's character ends up dying here too. The story in the novels also takes place in 1987 after the Cold War while the story in the books takes place after the Cold War. Moviemakers enjoy making Clancy angry don' they?

Jack Ryan And Marcus Cabot's Relationship

Sum of All Fears Ben Affleck Morgan Freeman

In Clancy's 1997 novel The Sum Of All Fears, Jack Ryan and CIA director Marcus Cabot have a rocky relationship. Cabot hates Ryan's guts. He thinks the agent is arrogant and too ambitious. Ryan, on the other hand, feels that Cbot is too laid back. As a result, the two never get along.

However, in the movie, Ryan (Ben Affleck) and Cabot (Morgan Freeman) end up having such a good relationship that Ryan takes him as his mentor. Events in the movie also take place in 2002 while the novel is set at a time when USSR is still intact.

Jack Ryan's Rank In The CIA

Ben Affleck dressed in black in The Sum Of All Fears

Also in the novel The Sum Of All Fears, Ryan is the Deputy Director of the CIA. Given that the president doesn't like him very much, he later decides to quit the agency to focus on rehabilitating his drinking problem. He also just wants to spend more time with his family.

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However, in the movie, Ryan is just a CIA analyst. His boss Cabot takes with him on assignment to Russia to inspect a nuclear weapons facility as part of an international treat agreement. There, he notices a few anomalies, including a couple of missing scientists.

Red October's Route

Marko Ramius (Sean Connery) and Jack Ryan (Alec Baldwin) take cover while being shot at in The Hunt for Red October

The Hunt For Red October starring a young Alec Baldwin as Jack Ryan and an established Sean Connery as the rogue Commanding Officer of "Red October" Captain Marko Aleksandrovich Ramius was almost faithful to the novel. However, since Hollywood has to do Hollywood things, there were some few alterations from the book.

For example, the scene where the submarine "Red October" cruising through the Penobscot River in Maine to a dock wasn't in the novel. The Royal Navy task force was also not included in the movie and neither was Jack Ryan's moments aboard HMS Invincible.

The Complicated Love Life

Cathy in The Sum of All Fears

Still, on The Sum Of All Years, the novel's take on Ryan and ophthalmic surgeon Cathy's relationship is different from the movie. In the novel, the two have been married for a while and they have two children. Cathy even wants a third child but hates her husband's alcoholism and work addiction.

Cathy also suspects that Ryan is having an affair. So, there's full family drama here. However, in the movie, they've only just started to date. The change is probably due to the fact that the movie is a reboot whereas the novel is a direct sequel to Clear And Present Danger.

New Career Paths

Jack Ryan (Chris Pine) with Cathy (Kiera Knightley) dressed up in Russia Shadow Recruit

In Jack Ryan: Shadow Recruit starring Chris Pine, the story isn't based on the novels at all. The movie is set after the 9/11 attacks. Ryan is in London studying at the LSE (London School of Economics). What? He later becomes a lieutenant for the US army and gets deployed to Afghanistan. What?

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He gets injured when his chopper is shot down and gets sent back to the US for treatment. There, he meets Cathy who is a medical student and not a surgeon. What? Okay. Enough with the whats. But 10 years later, Ryan has been assigned to Wall Street where he is going to take down the "Wolf Of Wall Street" Leonardo DiCaprio. That's a lie. He's actually working undercover to track terrorist financiers. Tom Clancy never imagined all this.

Different Terrorists With Different Ambitions

Morgan Freeman whispering to Ben Affleck in The Sum of All Fears

Back to The Sum Of All Fears. In the novel, Palestinian terrorists belonging to the Popular Front for the Liberation of Palestine (PFLP) seek the help of an East German physicist to build a nuclear weapon that will help destabilize the relationships between the Soviet Union and the United States. The plan to detonate the bomb during the Super Bowl.

In the movie, an Austrian Neo-Nazi attacks Baltimore using a nuclear weapon. He makes sure to link the attack to the Russians so that he can trigger a war between the United States and Russia. By doing this, he'll be able to establish a fascist nation in Europe.

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