Alice and Bob are on their way to Alphaville on the Alphaville Express, enjoying the scenery and thinking of all the Alphas they'll meet there. Bob heads to the baggage car since he forgot something ... just in time for the Beta Tribe to attack and make off with it. And Bob! A despondent Alice arrives in Alphaville to tell the story, and is informed that the Beta Tribe is the sworn enemy of Alphaville. Alice, friends with the Alphas, goes through a Lock and Load Montage and charges forth to save Bob. She breaks through the Beta Tribe perimeter ... ... and finds Bob in an ill-fitting borrowed Beta Tribe uniform, on his way to spy on Alphaville. Seems that the Beta Tribe has a few concerns about what Alphaville's doing. This is a Party Split. A party of heroes is separated (usually forcibly, but not always), and the story's focus stays on the principal--here, Alice--as that portion of the team meets one faction, and learns of the enmity with the other. Meanwhile, the separated sidekicks--here, just Bob--are persuaded (not 'persuaded', persuaded) to help the second faction. For this to be in effect, it's best that the split is not the actual objective of the second faction. Even if they take a sidekick or two as prisoner/hostage, it's not a kidnap/abduct mission, merely a side effect of the primary issue. (And why would the horrible evil Beta Tribe take a prisoner when all they want to do is murder everyone not of their own?) Also, it could be some other device that separates the groups. Just as long as it's not intended. Another note is that the factions need not be actually evil, just opposed; still, it helps if at least one is genuinely sympathetic. Finally, due to the nature of this trope ('Wait, those guys are good!'), spoilers are likely to be unmarked. Viewer beware. Examples:
- A Darkwing Duck episode, 'Apes of Wrath'. Darkwing meets Col. Trenchrot on his plantation while tracking down a missing scientist and is told of evil gorilla thieves, who then accidentally kidnap Gosalyn. The gorillas are allies of the scientist; Trenchrot is the actual villain of the piece.
- A Doctor Who episode, 'The Doctor's Daughter'. The Doctor meets humans fighting a war, when the Hath attack; during the attack, they take Martha Jones prisoner. (Remember the earlier caveat: they weren't trying to kidnap her, she just was taken prisoner as a side effect of the whole war thing.) The Doctor learns of the evil Hath from the humans; the Hath, however, 'tell' Martha of their side of the war. Neither are villainous themselves, and once the war is revealed as a HUGE mistake, (almost) all of them are more than happy to call it quits.
- A My Little Pony: Friendship Is Magic episode, 'Over a Barrel'. Twilight Sparkle is on the train with the rest of the cast, on their way to deliver a tree to the residents of Appleoosa; en route, Spike is with the tree when it's stolen by an attack from buffalo. Rainbow Dash and Pinkie Pie then break off to get Spike and the tree back ... and are told by the buffalo how they really need the land Appleoosa is on. Note here that the party splits into three: first Spike is separated and convinced, who then helps convince Rainbow Dash and Pinkie Pie when they arrive, and then all three help convince the rest of the cast. Again, neither faction are villainous as such.
- Occurred in Tsubasa Reservoir Chronicle at some point when the gang got transported to different parts of the same world. In Shara country, Sakura and Syaoran end up with a group of female performers who worship Ashura (I think) while Fay and Kurogane end up with some. . . male priests (I think) who worship Yasha.
- When they get transported back in time, they end up fighting on different sides of the war between the original Ashura and Yasha.
- In one episode of Supernatural Sam & Dean get separated and fall in with two separate bands of survivors, each of which thinks the other group is a bunch of demons.
- In Slayers NEXT, Lina and her group split up because they can't decide what to have for lunch. As a result Lina and Gourry go to a roast beef place while Amelia and Zelgadis go have hot pot. It is then both groups are recruited by two candidates for the leadership of the local magic guild. Both candidates are fearful that the other are going to play dirty tricks in securing the spot. It just be noted, it isn't about any ideals or whatever, but they only only work for the canadidates for some money. The two side do kinda still go to blows when they find out who's working with who... but a third party enters the picture, the previous head of the guild who was expelled by the two candidates for delving into immortality research.
- "The Lords of Quarmall", a Fafhrd And The Gray Mouser novella, has Fafhrd and the Mouser going their own ways temporarily, and each accepting a job offer from one of the opposing claimants to the throne of Quarmall.
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