Continuity mistake: Eddie snoops around the park of Cletus' old delinquent kids' home. He brandishes the torch with his left hand, but when he walks in a frame later he's holding it in his right hand. (00:00:48)
Continuity mistake: When Young Shriek blows Young Detective Mulligan's eardrum (just one for some reason), he grabs his own ear clutching his fingers around it. In the next shot his hand is turned around in a different way. (00:02:45)
Factual error: When we see Young Shriek struggling with Young Detective Mulligan, the gunshot explodes when the weapon is pointed up and at distance from her face. Obviously a direct shot to her eye socket would have killed her, but she is blind in that eye and has a scar in two distinct parts of the socket. It's hard to imagine how a wound with that pattern could have occurred even thinking of the bullet ricocheting off the top of the trunk or something. (00:02:55)
Continuity mistake: In the first "Present day" scene, the Ravencroft wardens enter Shriek's cell to feed her. She is lying on one side in the establishing dolly, and she's just lying on her back in the next shot. (00:04:10)
Audio problem: It is well-established that the symbiote can communicate with Eddie telepathically and others do not hear it. However, it can also speak normally and does so plenty of times; when the two are arguing in the bathroom of the prison, we see that Venom opens its mouth and move its 'lips', which would mean the woman in the stall and Detective Mulligan can hear him - which makes no sense in the scene. (00:06:30)
Continuity mistake: Venom is drawing hyper-fast parts of the material they ogled on the wall of Kasady's cell. On Eddy's messy desk there's a sheet with data from California State University, very recognizable for the colors and shape of the graph. When they draw the tree, notice that the sheet turns 90° multiple times between shots without Venom touching it. (00:10:50)
Plot hole: Venom has a photographic memory; he reproduces Kasady's sketch, an outline that matches perfectly a result (already on screen) of the google image-y search page for Rodeo Beach, California. Sure, it's a movie, but this plot device straight from Rise of Skywalker means that Kasady also had to have a photographic memory and that someone took a photo exactly from that one precise spot that happens to be also the exact one that showed up in "WebFindit." A couple of coincidences too many. (00:11:10)
Revealing mistake: If you look at the drawing in front of Eddie when he glances down at it after Venom typed in the name of the beach, it's only a crude draft of the one in close-up (it's missing the wave lines below the cliff outline, for instance). (00:11:20)
Continuity mistake: Venom 'saves' a woman that is being mugged; when they hold the evildoer upside down plotting to eat him, the woman witnesses the scene wide-eyed. Her necklace is in a different position between the background feature and the close-up on her. (00:16:40)
Continuity mistake: Eddie meets Anne at L'Araignee ("The Spider") and hugs her. His hand is at the top of her shoulder, middle of the back, top of the shoulder again. (00:18:45)
Continuity mistake: At the beginning of the "Let's Call The Whole Thing Off" scene, Eddie already poured the orange juice and put it down before Venom messes with the radio and fridge. We see then symbiote's tentacle pass in front of Eddie's hand, which is suspended in mid-air still pouring. Then we cut back to the original angle and Hardy is about to drink from the glass, the orange juice carton well set on the table. (00:23:05)
Continuity mistake: When Venom delivers the mail to Eddie while making breakfast, the letters are angled differently in the various shots, in Venom's cute little pseudo-hand first, between Tom Hardy's big paws after. (00:23:40)
Other mistake: When Eddie reads Kasady's letter, it's obvious that the whole speech can't fit inside the postcard. Moreover, parts of it don't even make sense since Eddie could never "see" the part about Shriek; he knows nothing about her at that point of the movie. Finally, either way when we see him read the letter, the parts shown don't match the narration; for instance when he gets to the part about Kasady's heart stopping, it is on the part of the postcard opposite of the one he's 'reading'. (00:24:25)
Revealing mistake: Kasady squishes a spider that is walking on the postcard. The splattered blotch, strictly divided in red and black, is disproportionately large for the size of the insect. (00:25:35)
Continuity mistake: When Venom starts tossing Kasady around in his cell, Eddie right hand is positioned in the rightmost space of the door. Kasady bites him when his arm is through the space to the left of that, though. His arm is also pointed at a different angle and height between shots. (00:29:35)
Other mistake: Venom and Eddie are having a domestic dispute. Items rain off the window in front of a homeless person. The other passers-by change between shots. Not only that; in the second shot there's one extra who turns around acting startled by the man's shout. Does not really make sense; heavy objects just crashed down a few feet from him, anyone would have been startled by that first and foremost. Wrong reaction time/ direction of the extras. (00:32:45)
Continuity mistake: When Eddie shouts "No!" as the free symbiote vandalizes his bike, he sticks his head out from an apartment completely in the dark, but we saw him run towards the window near the only part of the flat where there are lights still functional and switched on. (00:34:30)
Other mistake: Eddie witnesses in horror from the window his former alien partner wrecking his Ducati bike in the alley below. Venom exits stage right and possesses a lady riding a bicycle, headed towards his right. Somehow, this double *right* turn leads to Eddie witnessing Venom's middle finger from a window to the *left* of his original position. (00:34:30)
Audio problem: Eddie Brock is trying to find where Carnage might be headed. To draw inspiration he listens to the recording of the last time they spoke (when incidentally he was never seen retrieving the tape). However, the lines in the recording are different takes from the original scene, spoken at a brisker pace without dramatic acting pauses. (00:38:00 - 00:42:40)
Continuity mistake: Carnage pins against the wall a prison warden who begs him to spare him. He looks straight ahead and the POV shot displays Carnage's face directly in front of him, but in the side view Carnage's splotchy eyes are in front of the chest of the guy and the tongue has to go up a lot to plunge inside the victim 's oesophagus. (00:38:15)
Answer: It is deliberately never shown on screen, so unless it gets answered in a sequel the audience is left to speculate. Mulligan does come into direct contact with Carnage since Cletus is the person who kidnapped him. In addition, the fight between Venom and Carnage takes place all over the church with the pair constantly stabbing, slashing, and bludgeoning each other. A piece of either symbiote could be somewhere in that building. Again, though this is just speculation since it's never shown how Mulligan is infected.
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