Deciding to do something

In Wikipedia plot summaries, fictional characters frequently decide a course of action. You can remove the bit about making a decision:

• "The thief decides to steal the painting and begins to formulate a plan." → "The thief formulates a plan to steal the painting."
• "Deciding to challenge the dragon, the knight gathers his courage for an attack." → "Gathering his courage, the knight attacks the dragon."
• "The cop makes his move to kill the outlaw, shooting him in the head." → "The cop shoots the outlaw."

You don't have to describe every step of the process. In more complex scenarios, you may be able to streamline the preparatory phase by rewording. Depending on the context of the scene and the themes of the work, you might also be able to streamline later phases.

Successful attempts

A related concept is the successful attempt. If it's obvious, there's no reason to tell us that the attempt is successful:

• "The knight manages to slay the dragon." → "The knight slays the dragon."
• "The thief attempts to flee; successful, she returns to her base." → "The thief flees to her base."

If the attempt failed, you can often simplify that, too:

• "The thief attempts to flee, but a cop catches her." → "A cop catches the fleeing thief."

Starting to do something

Is it necessary to tell us that someone has "started to" row a boat? Why not just say that he's rowing the boat?

• "The child prodigy starts to operate the submarine without ever having learned how to operate it." → "The child prodigy operates the submarine without training."

Setting and year

People like to explicitly state the setting of a story even when it's irrelevant. The worst writing uses "in the year", which is pointlessly verbose.

• "The story takes place in the city of London in the year 1522." → "In 16th century London, ..."
• "Far in the future, in the year 2760, a thief plots her heist." → "In 2760, a thief plots her heist."

In-universe dates are probably extraneous details.

• "In Galactic Year 882, the evil emperor is crowned. In Galactic Year 892, the space knight begins his quest to depose the emperor." → "Ten years after the evil emperor is crowned, the space knight begins his quest to depose him."

Identifying scenes and transitions

The goal is to describe a film's plot, not its editing. Identifying specific scenes or transitions is unnecessary.

• "The film begins with a dramatic showdown at noon between two gunfighters." → "Two gunfighters duel at noon."
• "Later, a cop arrests the conspirators. In the next scene, they escape from jail." → "A cop arrests the conspirators, but they escape from jail."
• "In the opening scene, a mother swears revenge for her son's death." → "A mother swears revenge for her son's death."
• "The film ends as the lovers reunite in the final scene." → "The lovers reunite."
• "The men are shown fleeing." → "The men flee."

Post-credits sequences are usually throwaway gags and probably not worth mentioning. If the sequence is important, integrate it into the summary as normal; there's no need to mention that it comes after the credits.

Adverbs and adjectives

The quickest and easiest way to streamline a plot summary is to strip out unnecessary adjectives and adverbs. You need to use your judgment, but you can often tell a sentence is too flowery when it has multiple modifiers.

• "Deep within the cavernous cave, the enormous dragon roars angrily when it sees the intrepid knight purposefully approach." → "The dragon roars as the knight approaches."
• "In a surprising upset, the amateur somehow outscores the expert." → "In an upset, the amateur outscores the expert."

If the plot is short enough, you can let through some extra detail. If it's 1000 words, then the flowery words should be the first casualties.

Modern English is a weird language with German, Greek, and Latin roots. There's almost always a way to rephrase imprecise words instead of using modifiers:

• "The boy sees a dead body." → "The boy sees a corpse."

"Body" is a word of Germanic origin that can refer to living or dead people; "corpse" is a word of Latin origin that can only refer to a dead person.

Streamline modifiers that don't add useful detail:

• "Driving at high speed, the car is hit by a herd of deer." → "The speeding car hits a herd of deer."

One doesn't need to explicitly mention that this car is being driven, and using the adjective "speeding" is more concise. Flipping the subject and object changes the scene in what is probably an inconsequential way.

Countdowns and timelines

These are endemic in thrillers where some nasty event will take place in exactly one week. Variations include ghost stories where the protagonists are cursed and will suffer a horrible fate in one week, a police thriller where time counts down until a bomb goes off, a crime thriller in which a parent has a limited amount of time to rescue a child, etc. Let's focus on the ghost story:

• "(DAY ONE) Although the couple scoff at the curse, they experience unexplainable phenomena." → "Although the couple scoff at the curse, they experience unexplainable phenomena."
• "On Thursday (day six of the curse), the couple become frantic." → "On Thursday, the couple become frantic."

Often you can compress day-by-day reports into a sentence or two. For example, assume that the first 20 minutes of a feature-length film depict a couple who slowly come to believe in a supernatural curse. You need to speed through this to describe the main plot, which takes up the remaining runtime: "Although initially skeptical, the couple experience unexplainable phenomena. By the end of the week, they have become frantic." Those 18 words can replace an entire paragraph of unwarranted detail in a 1500+ word plot summary.

Quotations and catchphrases

Generally, these don't add anything to the reader's understanding of the plot. Iconic catchphrases might be warranted, but others should probably be moved to Wikiquote. In most cases, it's possible to paraphrase a quotation down to half its original length. Keep in mind that quoting any specific bit of dialog will place potentially undue emphasis on it.

• "As the cop listens to the tape, he recognizes the corrupt banker through his catchphrase, 'You can bank on it!'" → "The cop recognizes the corrupt banker on the tape."

Detailed descriptions of death scenes

In horror films, especially slasher films, it's traditional to spend much of the runtime on gory deaths. Fans often like to embellish these scenes with too much detail, such as the exact manner of death. In a long plot summary, this can be removed.

• "The masked killer crashes the teens' party. In the resulting hysteria, he decapitates Bob with a machete, stabs Betty with a Bowie knife three times in the heart (just like Betty's father did to the killer's mother), and chases after Jane after she escapes through the back door." → "The masked killer crashes the teens' party. In the resulting hysteria, he kills Bob and Betty. Jane escapes, and he chases her."

Romantic prose

People sometimes like to amp up the romance. You can save a few words by making the descriptions more matter-of-fact.

• "They share a kiss." → "They kiss."
• "The two lovers passionately lock lips." → "The two lovers kiss." (Or, even better yet, "They kiss.")

Unless it's terribly important to the plot, you can replace detailed descriptions of sex acts with "they have sex". Editors sometimes emphasize characters' nudity, which may be irrelevant to the plot.

Speculation, extrapolation, and interpretation

Don't speculate about the implications of plot events, try to extrapolate from them, or make personal interpretations. Be careful not to violate WP:FILMPLOT: "Do not make analytic, synthetic, interpretive, explanatory, or evaluative claims about information found in a primary source." Instead, summarise what concrete information the film gives us and no more.

• "Richard smiles at Susan, suggesting that he has forgiven her." → "Richard smiles at Susan."
• "Smith falls off the cliff, and presumably dies." → "Smith falls off the cliff."

Show, don't tell

Show, don't tell is a writing style that favors implying information rather than explicitly stating it. It's more evocative and creative, but it takes more words to convey the same information. When you're summarizing a complex work into several hundred words, it's frequently best to avoid this. Instead, simply and explicitly state everything. Remember to avoid original research and personal analysis of the work as much as possible.

• "The knight staggers in the dragon's dark lair, unsure of where his prey lies until its flames illuminate the cave." → "The knight uses the dragon's flames to track it in the dark cave."
• "The collector frowns as he surveys his art collection. The next day, he hires a thief who has stolen great treasures from around the world." → "Unsatisfied with his current collection, the collector hires an experienced art thief."

This writing style is most commonly found in a long, descriptive paragraph rather than a single overwritten sentence. In these cases, you can often replace the entire paragraph with a single sentence that explicitly states the central idea. For example, if a paragraph shows how a character becomes increasingly stressed, replace it with "Bob becomes increasingly stressed". This is unnecessary in shorter plot summaries.

Passive voice

As much as English teachers hate passive voice, it's a legitimate part of English. When it's used unnecessarily, it bloats a sentence. You can reword these sentences to use active voice:

• "The thief is chased by a cop." → "A cop chases the thief."

Sometimes long sentences are written in passive voice so that the writer can string along several clauses:

• "The bank is robbed by a thief who is later revealed to be an employee." → "A thief, later revealed to be an employee, robs the bank."
• "The dragon is slain by a knight from a neighboring kingdom ruled by an elf queen." → "A knight from a neighboring kingdom slays the dragon."

It might take a bit of work to disentangle the phrases, order them properly, and decide which details are extraneous. If the elf queen doesn't figure any further in the story, why even mention her? Use your judgment.

Editors may also use passive voice to "zoom out" and describe a scene out-of-universe:

• "The family is seen trekking through America." → "The family treks across America."

This often happens when describing the final scene of a film.

If the subject is obvious or unknown, you can also use passive voice to streamline a sentence:

• "A prison guard shoots and kills the escaping prisoner." → "The escaping prisoner is shot and killed."
• "An unknown assailant ambushes the cop." → "The cop is ambushed."

Purple prose

Purple prose overwhelms the reader with unnecessary detail written in flowery language. Remember "it was a dark and stormy night..."? That's purple prose. Although purple prose is traditionally found in creative writing, excessively detailed and flowery writing can creep in anywhere. Sometimes the opening or closing scene of a work is described in loving detail:

• "As a heavy storm in the distance threatens to enter the city, the camera slowly pans up from a pair of high heeled shoes as a 45-year-old, dark-haired woman who is wearing a mink fur coat gingerly steps out of a 1965 Chevrolet Corvette just as a fair-skinned man wearing a blue hat and coat speeds by her on a customized 1964 Harley-Davidson motorcycle, splashing mud on the woman's fur coat and drawing her ire." → "A man on a motorcycle splashes mud on a middle-aged woman's fur coat."

Poetic clichés and metaphors are also good candidates for pruning. While they may make you sound creative and intelligent, it's often easier to flatly state something rather than get poetic about it.

• "The suspect chases the detective through the sewer, and the hunter becomes the hunted." → "The suspect chases the detective through the sewer."
• "The icy jaws of death begin to close around the knight during his climactic fight." → Who knows. Probably just remove it.

Jargon

Normally, you want to avoid unnecessary jargon. In a plot summary, where you have limited space, you might choose technical terms over their more simplistic alternatives. Remember to wikilink terms that may not be understood in context.

• "A mobster gives the mercenary a variety of weapons as well as a UN passport that has to be injected under the skin of the neck." → "A mobster gives the mercenary a variety of weapons and a subdermally implanted UN passport."

In this case, I decided "subdermal" was not technical enough to bother linking, but others may disagree, obviously.