History Recap / StarTrekTheNextGenerationS5E18CauseAndEffect

* GettingCrapPastTheRadar: Data's reference to the voices including "romantic encounters" reflects the greater reluctance of the franchise, at least until the Series/StarTrekDeepSpaceNine years, to use the word "sex" on screen.

* ConvenientlyEmptyBuilding: An unusual variation occurs when the ''Enterprise'' vents the atmosphere of the main shuttlebay as an emergency means of maneuvering to avoid a collision. The main shuttlebay was never shown on-screen for budgetary reasons, but it is by all accounts a huge, busy facility; but there was absolutely no mention of the fate of the personnel who happened to be in the shuttlebay at the time—and due to the urgency of the situation, could not be warned or given time to evacuate.

* GroundhogDayLoop: [[OlderThanTheyThink Predating]] the TropeNamer by over a year.

We begin this episode InMediasRes, with the ''Enterprise''[='=]s engines on fire and the ship out of control. The bridge crew is frantically trying to steady the ship long enough to launch the lifeboats as Picard orders all hands to abandon ship. And just as the audience is thinking, "LikeYouWouldReallyDoIt," they [[GutPunch really do it]]: the ''Enterprise'' [[WhamShot vanishes in a huge]] [[ExplosionsInSpace space explosion]].

Back in that unexplored sector, back to the poker game. Worf experiences ''[[PardonMyKlingon nIb'poH]]'', and Crusher attempts to predict the hand that Data is about to deal. Instead, he deals all 3s, then three of a kind to each. Crusher is called to sickbay to help La Forge deal with a dizzy spell; she inspects his VISOR on a hunch and finds that it is being affected by TechnoBabble. In Engineering, Data runs a diagnostic on ship's systems, and the results come up all 3s. They get a call from Crusher, telling them she's just recorded a mass of disembodied voices in her quarters--[[BrickJoke and they hear a glass shatter]].

* DejaVu: The crew are caught in a GroundhogDayLoop, Doctor Crusher begins to experience ''déjà vu'', and so do the other crew members when she brings up the issue. In subsequent loops, this progesses to predicting events before they happen.

* FateWorseThanDeath: It is heavily implied that the ''Bozeman'' crew have relived their own loop for the better part of a century--though unlike the ''Enterprise'' crew, whether they are at all aware of it is left unclear.

** Beverly calls Riker on a bluff in the first scene with the card game, saying she had a feeling he was bluffing. Knowing that Riker has the best poker face on the ship, it's a little clue that Bev was "remembering" previous iterations of the game.

* PinocchioNose: After calling Riker's bluff, Crusher tells him that his left eyebrow raises when he bluffs--except she's just kidding.

** Downplayed. Crew members do not entirely remember previous loops, but do experience DejaVu moments, which grow in intensity with each new iteration.

* WhatYearIsThis: Inverted. Picard asks Captain Bateson what year he thinks he's in, with Bateson assuming it's still 2278. The ''Enterprise'' crew also has concerns about this for themselves, but are relieved that it hasn't been anywhere near that long for them (only about 17 days) when they ring up a timebase reading.
* YouCantFightFate: Dr Crusher very deliberately tries to avoid breaking her glass in the next loop but just ends up breaking it another way. It achieves BrickJoke status when Geordi contacts her on the intercom, and in the background you hear a glass breaking.

[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/tng_cause_and_effect_hd_380.jpg]]
[[caption-width-right:350:''"Do you have the feeling that you've done this before?"'']]

->''"All hands abandon ship! Repeat, all hands abandon--"'' '''''[[KilledMidSentence (BOOM!)]]'''''
-->-'''Picard''', saying something viewers will get used to hearing a few times.

We begin this episode InMediasRes, with the ''Enterprise''[='=]s engines on fire and the ship out of control. The bridge crew is frantically trying to steady the ship long enough to launch the lifeboats as Picard orders all hands to abandon ship. And just as the audience is thinking "LikeYouWouldReallyDoIt", they [[GutPunch really do it]]: the ''Enterprise'' [[WhamShot vanishes in a huge]] [[ExplosionsInSpace space explosion]].

Act I seems to be a HowWeGotHere, as we're re-introduced to the ''Enterprise'' entering an unexplored sector. We first look in on Riker, Data, Worf and Crusher engaging in their regular poker game. After much banter (and a win for Crusher, who calls Riker's bluff), Crusher is called to sickbay to help La Forge deal with a major dizzy spell — but she experiences a bit of ''[[Main/DejaVu déjà vu]]'' whilst treating him. Later that night, in her quarters, Crusher hears what seem to be a mass of disembodied voices and, in switching on the light, breaks a glass she'd left on the night stand.

Crusher reports her experiences to the rest of the senior staff, but is interrupted when sensors detect a NegativeSpaceWedgie nearby. As the bridge crew attempt to deal with the situation, the ship begins losing power and is unable to move — just as a starship emerges from the Space Wedgie on a direct collision course. With no power to the engines, Riker (standing at Data's side for no apparent reason) suggests decompressing the main shuttlebay to provide the necessary thrust to get out of the way, while Data counter-suggests using the tractor beam to push the other ship aside. Picard goes with Data's plan, which is not entirely successful; the other ship is deflected, but not by enough, and smashes the ''Enterprise''[='=]s warp nacelle. This quickly causes a series of catastrophes and the events of the teaser play out before us again and the ''Enterprise'' is destroyed.

Act II re-re-introduces us to the ''Enterprise'' entering an unexplored sector; it's at this point that savvy viewers will recognize the GroundhogDayLoop at play. Again we visit Riker, Data, Worf and Crusher playing poker, with much familiar banter. Crusher is about to win when Riker folds, realizing that she is going to call his bluff. Crusher is called to sickbay to help [=LaForge=] deal with a major dizzy spell — and again experiences ''déjà vu''; only this time, La Forge feels it as well. Later that night Crusher again hears voices in her quarters and quickly calls the captain — breaking that glass once again.

Act III. The ''Enterprise'' enters an unexplored sector. By this time, even the characters are starting to catch on, after a fashion; at their poker game, Worf recognizes their banter; and then he, Riker and Crusher correctly call out the hand Data is dealing even before he deals it.

-->'''Data:''' "[[{{Understatement}} This is highly improbable.]]"

The next morning, Crusher and La Forge fill the others in on what they think is going on: a NegativeSpaceWedgie is going to entrap the ''Enterprise'' in a GroundhogDayLoop. They listen to parts of the recording which suggest the severity of the encounter's outcome, while trying to think of a way out. The problem is (unlike most instances of this trope) that if/when the Loop "loops", they all lose their memories of the previous loop, except for feelings of ''déjà vu''. La Forge suggests rewiring Data's AppliedPhlebotinum to mirror the previously established TechnoBabble so that, if/when the Loop "loops", he can send a message into the next loop — albeit an extremely short one, one word at most, which will show up only as a sort of post-hypnotic suggestion so Data won't know initially what it means. The plan is carried out, and no one feels like they've tried this before, which is a good sign. RedAlert! NegativeSpaceWedgie! Ship on collision course! The tractor beam doesn't work! ''Enterprise'' explodes! Only this time Data manages to activate the TechnoBabble message at the last second.

Back in that unexplored sector, back to the poker game. Worf experiences ''[[PardonMyKlingon nIb'poH]]'', and Crusher attempts to predict the hand that Data is about to deal. Instead, he deals all 3s; then, three of a kind to each. Crusher is called to sickbay to help La Forge deal with a dizzy spell; she inspects his VISOR on a hunch and finds that it is being affected by TechnoBabble. In Engineering, Data runs a diagnostic on ship's systems, and the results come up all 3s. They get a call from Crusher, telling them she's just recorded a mass of disembodied voices in her quarters — [[BrickJoke and they hear a glass shatter]].

As before, the ship is without power and unable to move as another ship emerges from the Wedgie. Riker (standing at Data's side for no apparent reason) suggests decompressing the shuttlebay but Data counter-suggests using the tractor beam to push the other ship clear. Picard sides with Data, but Data suddenly has a EurekaMoment and goes with Riker's plan instead; the main shuttlebay decompresses, pushing the ''Enterprise'' clear and allowing the other ship to pass safely. The NegativeSpaceWedgie vanishes, power is restored and the ''Enterprise'' crew greet the crew of the U.S.S. ''Bozeman'' (commanded by none other than Captain [[Series/{{Frasier}} Frasier]] [[Series/{{Cheers}} Crane]]), which was either stuck in the Loop for some 90 years or got teleported by the rift 90 years into the future. Data explains his EurekaMoment: glancing at Riker, Data noted the number of rank pins on his collar (3) and deduced that the various phantom 3s referred to Riker, indicating that Riker's plan would be the successful one. Good thing he didn't think it referred to himself, since he is 3rd in command of the ship behind Riker and Picard.

!!Tropes featured:

* BottleEpisode: Sets on the Enterprise are all reused sets, the ''Bozeman'' is a retooling of the USS ''Reliant'' from ''Film/StarTrekIITheWrathOfKhan'', and Bozeman's interior is from the recently produced ''Film/StarTrekVITheUndiscoveredCountry''. Creator/KelseyGrammer's guest appearance is the only aspect that deviates from this trope.
* BrickJoke: At the start of each time loop, Riker wonders aloud if Data is using his high-speed shuffling ability to stack the deck. In the final loop, that's exactly what Data does (albeit subconsciously).
* CallBack: ''[[Recap/StarTrekTheNextGenerationS3E15YesterdaysEnterprise Yesterday's Enterprise]]''. That episode featured a Federation ship from the past stumbling through a time rift as well.

* DejaVu: The crew are caught in a GroundhogDayLoop, Doctor Crusher begins to experience ''déjà vu'' and so do the other crew members when she brings up the issue.

* FateWorseThanDeath: It is heavily implied that the ''Bozeman'' crew have relived their own loop for the better part of a century.

* [[FlingALightIntoTheFuture Fling a Light Into the Next Temporal Loop]]: How they end up saving the ''Enterprise''.

* HearingVoices: Caused by timelines bleeding over.

** Each loop takes roughly a day, and they find out at the end they're out of sync by seventeen days. So the episode opening destruction is roughly the twelfth time it was destroyed.

* RippleEffectProofMemory: Downplayed. Crew members do not entirely remember previous loops, but do experience ''déjà vu'' moments, which grow in intensity with each new iteration. [[Literature/StarTrekDepartmentOfTemporalInvestigations One of the]] ExpandedUniverse novels also mentions that the ''Bozeman'' crew experienced the same effect, but didn't have the knowledge to break themselves free like the ''Enterprise'' did, resulting in [[FateWorseThanDeath 90 years of feeling trapped in a perpetual cycle of death]].

* TooMuchInformation: When Data is summarizing his analysis of the "overlapping voices" phenomenon that Dr. Crusher recorded, Picard cuts Data off when he ends up listing the number of couples who he determined were engaged in "[[CoitusUninterruptus romantic encounters]]".

* WhamShot: The ''Enterprise-D'' going kablooey in space in the cold open.
* WhatYearIsThis: Inverted. Picard asks Bateson what year he thinks he's in, with Bateson assuming it's still 2278. The ''Enterprise'' crew also has concerns about this for themselves, but are relieved that it hasn't been anywhere near that long for them when they ring up a timebase reading.

* CallBack: ''[[Recap/StarTrekTheNextGenerationS3E15YesterdaysEnterprise Yesterday's Enterprise]]''. That episode featured a Federation shipship from the past stumbling through a time rift as well.

->''"All hands abandon ship! All hands abandon--"'' '''''[[KilledMidSentence (BOOM!)]]'''''

->''"All hands abandon ship! All hands abandon--" '''''[[KilledMidSentence (BOOM!)]]'''''

* StableTimeLoop: When Riker suggests that reversing course could be the cause of the ship's destruction, he is implying, whether he realizes it or not, that this trope is in effect. The irony is that [[AvertedTrope it isn't]], and had the crew not been overthinking the situation in this way, they might have broken free after the first loop.[[note]]Though it's also possible that the spacial rift was drawn to the ''Enterprise's'' position, not a static point in space, in which case it would make no difference.[[/note]]

* TooMuchInformation: When Data is summarizing his analysis of the "overlapping voices" phenomenon that Dr. Crusher recorded, Picard cuts Data off when he ends up listing the number of couples which he determined were engaged in "[[CoitusUninterruptus intimate encounters]]".

* YouCantFightFate: Dr Crusher very deliberately tries to avoid breaking her glass in the next loop but just ends up breaking it another way. It achieves BrickJoke status when Geordi contacts her on the com, and in the background you hear a glass breaking.

* BottleEpisode: Sets on the Enterprise are all reused sets, the Bozeman's exterior is directly from ''Film/StarTrekIITheWrathOfKhan'', and Bozeman's interior is from the recently produced ''Film/StarTrekVITheUndiscoveredCountry''. Creator/KelseyGrammer's guest appearance is the only aspect that deviates from this trope.

* NothingIsScarier: done extremely effectively with the poker game that begins Act I. We've just seen the ''Enterprise'' explode and the entire main cast die... and the first scene afterwards does not address that fact in the slightest. It isn't until the next scene, with Crusher and La Forge in Sickbay, that we get any indication that anything is wrong.

* CallBack: Geordi proclaims the ''Enterprise'' has a coolant leak in the same way he did in ''[[Recap/StarTrekTheNextGenerationS3E15YesterdaysEnterprise Yesterday's Enterprise]]''. That episode featured a Federation shipship from the past stumbling through a time rift as well.

* CallBack: Geordi proclaims the ''Enterprise'' as a coolant leak in the same way he did in ''[[Recap/StarTrekTheNextGenerationS3E15YesterdaysEnterprise Yesterday's Enterprise]]''. That episode featured a Federation shipship from the past stumbling through a time rift as well.