The now-defunct studio, Anabolic, had a gang bang series called "The Gangbang Girl" that ran from 1992 through to 2007 and spanned 37 additions. A lot of those had a bit of a plot. This contrasts with the sister studio, Diabolic, which had a line called "Gang Bang Auditions" which I have no recollection of any of them having a plot.
From the Diabolic series, a few notable ones that I recommend are:
GBG 1 - Trixie Tyler - the overall plot of this movie is that Trixie is in Los Angeles visiting an old friend of the family who just happens to be a photographer. In the first scene, the family friend brings Trixie to a local bar and he's hoping that something will happen that he can photograph and sell the pictures to Gang Bang Magazine. Well, as luck would have it, a gangbang does happen, and we can presume that the photographer sold his photos. One reason I go back to the scene occasionally is because the acting and voiceovers are so cheesy. It's worth watching just to see the bad acting. The remainder of the scenes all have thin plots as well, such as Trixie going to the gym or Trixie having a surprise party with a bunch of naked guys. When this title was first released in 1992 it was in two parts, but I think some places package it as one title now.
https://www.iafd.com/title.rme/title=gangbang+girl+1/year=1992/gangbang-girl-1.htm
GBG 2 - Debi Diamond - in the first scene, Debi is playing a teaching assistant who is teaching a course in abnormal psychology. As regularly happens on every university campus, a gang bang breaks out. Then again, Debi was probably just being a good teacher considering that gang bangs would be considered abnormal by most people.
https://www.iafd.com/title.rme/title=gangbang+girl+2/year=1992/gangbang-girl-2.htm
I think it's the third scene in this title that doesn't really have a plot but it's worth mentioning. My memory might be a bit off, but I think it is staged as Debi having a fantasy and taking on a bunch of guys in a smoky room with many of them wearing masks. What I like about this scene is that a lot of the guys come while wearing a condom and in most cases the guys will remove the condom and dribble the cum onto Debi's face or into her mouth. In a few instances, Debi bites the end off a condom and sucks the cum out. As with GBG 1, this was originally released in two parts but I think most places stream or sell it as one title now.
GBG 24 - Inari Vachs - full disclosure, I am a big fan of Inari, and my opinion of the scene may be skewed by that. This is one of my favourite scenes from the entire series. Inari and her husband are sitting home when a group of guys comes bursting in, but an important part of the plot is that this is all staged as part of a fantasy, though it's somehow set up by her husband. They rough her husband up and then have their way with her.
The second scene in GBG 24 is with Layla Jade and Maren Beautte. This is a strange continuation of the plot in the first scene with Inari. The husband from the first scene arrives at a construction site to collect $500 from the ringleader who gang banged his wife. The reason why the husband is being paid and not the other way around is beyond me, but it doesn't ruin the scene. The husband has his daughter and his daughter's friend in the car with him and a deal is struck where for $20 each, the 14 guys at the construction site can have their way with the daughter and her friend. Probably the most notable part of this scene is that it finishes up with the girls being taken into a portable toilet with Jade getting her head pushed into the opening and eventually all the guys come with several of them coming right on the toilet seat which Jade licks off.
https://www.iafd.com/title.rme/title=gangbang+girl+24/year=1998/gangbang-girl-24.htm
GBG 27 - Justine Romee - Justine plays a stripper who attends a bachelor party. Justine goes around giving lap dances and eventually the guys get a little bit to touchy-feely so Justine threatens to shut the show down or renegotiate her fee to include getting gang banged. Money changes hands and balls get drained.
Aurora Snow and Kamy - this is the second scene in GBG 27 and is also one of my favourites from the series. Aurora and Kamy are working in a concession stand at an arena. There's obviously nothing going on because only the maintenance crew is around. The guys start hassling Aurora and Kamy which causes them to run around the arena, chased by the guys. Kamy gets into it and goads the guys along by stripping and tossing her clothes aside. The girls end up running onto the arena floor from opposite sides and Aurora is shocked to see Kamy wearing only her panties. Aurora asks, "what are you doing?" And Kamy responds by saying "it's obvious we are going to get fucked so we might as well enjoy ourselves." I found this scene to be a bit unusual in that both Aurora and Kamy were known for their anal performances, but Aurora doesn't do anal in this scene.
https://www.iafd.com/title.rme/title=gangbang+girl+27/year=2000/gangbang-girl-27.htm
The last scene that comes to mind for favourite plot-based gang bang scenes stars Carter Cruise. It's for the New Sensations Studio in a series they called "Tales from the Edge." The name of the specific DVD was called "Fantasies." In this scene, Carter and several guys are sitting around playing cards lamenting that they are all graduating from college and likely won't ever see each other again. Carter ups the ante by suggesting they play strip poker, and they do. One of the guys takes Carter to another room for some fun and the rest of the guys eventually join in. The acting is quite good in this scene, and I highly recommend finding it. Unfortunately, it doesn't appear to be available on the New Sensations site anymore, but it is still widely available.
https://www.adultdvdtalk.com/review/fantasies-new-sensations-34178
https://promo.newsensations.com/product_info.php?cPath=1160&products_id=3025&
I'll look forward to seeing some other suggestions.
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