Continuity mistake: When John and Roy walk into the house with the pregnant gunshot victim, only John's wearing a helmet and he places it on the floor near the victim's husband, but in all of John's closeups (from the unusual POV looking up at him) his helmet is on the counter. Additionally, there are blue glasses upside-down on the side of the dish drainer, but in those closeups of John the glasses have vanished, and the glasses vanish again when Roy helps the husband get on his feet. Also notice that there's now a blue glass in the sink.
Visible crew/equipment: In the locker room, after Chet tells Johnny that he knew all about the practical joke, when they walk to the door together there's a quick glimpse of the cameraman's reflection on the door's glass, before John tells Chet about the fictitious five dollar bill down by Mike's locker.
Continuity mistake: There are only two ambulance attendants who take the pregnant gunshot victim to the vehicle, but en route we see two attendants in the front seat - driver and passenger, and a third attendant is in the back with John and the victim. Then when they reach Rampart, the attendant that was in the back with John has vanished and he's the one who opens the back door from the outside. As an aside, in the ambulance, when John talks to Rampart about fetal heart tones, we see the attendant is actually mucking around with the IV drip.
Visible crew/equipment: When Roy and John get back to the station, and Marco walks up to the squad to talk to the guys about the practical joke they're going to play on Chet, on the squad's spotlight we can see the reflection of the camera, which is in front of the map.
Visible crew/equipment: When Station 51 is dispatched to a man trapped at World Picture Studios, just after they pass the studio's gate, in the moving shot from the left side of Squad 51, the reflection of the cameraman is visible on the lightbar atop the squad's roof.
Visible crew/equipment: After the fake eye exam 51's guys are sitting around the kitchen table, and when Chet tells them that he was sitting in the front row at the movies, there are moving shadows at the bottom, right corner of the screen, which do not belong to the guys.
Continuity mistake: When Johnny is writing the 'for sale' sign about his Land Rover, in the wide shot the two phone numbers begin with "853" and "352", but in the closeup a piece of paper has been glued over the phone numbers, and the new numbers now begin with "321" and "749."
Visible crew/equipment: When Roy and Johnny are trying to get the basketball player (Kareem Abdul-Jabbar) out of the car, and when Roy exits the car to get equipment, the outlines of the mic transmitters and wires are visible on the back, left side of Johnny's shirt, and back, right side of Roy's shirt.
Deliberate mistake: During the rescue of the car at the top of the draw bridge, The Boat approaches and radios in to say that they have a diver standing by. Then after Johnny shouts, "Are you all right?" the rescue boat is shown again, but this time it's a flipped shot - note that everything is reversed from the prior shot.
Visible crew/equipment: After the rescue on the draw bridge, when Squad 51 gets back to the station Roy goes to the backyard and sits in the sports car, and in this shot just as we hear Johnny's footsteps, on the Land Rover's window we can see the reflection of a crew member who is moving backwards.
Visible crew/equipment: When Johnny and Roy are at the top of the open drawbridge, beside the car hanging over the edge, just after Roy says "Be careful, this could go at any minute," the moving shadows of the cameraman and another crew member are visible on the bridge surface. That shadow is visible in two other previous shots from the same angle.
Continuity mistake: When 51's guys are at the table eating and discussing Roy and Johnny's deal, Johnny tosses his car keys to Roy, and in the following shots those keys vanish and reappear on the table repeatedly, and in the shots where the keys appear on the table, it's the ketchup, mustard, and napkins that have vanished. Also notice that the ketchup's brand name is covered.
Deliberate mistake: When O'Brien shows up at the nurses' station for Dixie's answer, after she declines the offer Dixie walks off to a patient who's brought in by the police, and the last closeup that's shown of O'Brien is flipped - note his hair is parted the opposite way and the background is backwards.
Revealing mistake: When Johnny and Roy are at the top of the open drawbridge, Johnny is wearing a watch on his left wrist, but when his stunt double rescues the woman in the car dangling off the edge, he is not wearing a watch. Additionally, the stuntman's pompier belt has a large axe sheath attached to it, but Johnny's life belt does not, and the stuntman's arms are much hairier, as usual.
Plot hole: At the end of the episode, when Johnny tells the guys that he sold one of his photographs for $25, Chet claims the money is his and points to everyone in the photo, noting that Captain Stanley, Marco, Mike, Roy and Johnny are all in the photo but Chet's not, which means he's the one who actually used the camera and snapped the photo. However, the itty bitty problem here is that earlier in the episode, during the rescue, we can see that after Marco heads up the hill that it's actually Chet who's with Mike, Johnny, and Roy carrying the victim up the side of the hill, alongside Captain Stanley. So the only one who could have really taken that photograph was Marco, which completely contradicts the whole bit at the end.
Revealing mistake: When they wheel the stretcher with the unconscious teenager from the school fire into treatment 3, the stretcher is pushed up against the ER's gurney, and when the teen's right arm gets caught between the stretcher and gurney, the supposedly unconscious teen moves his arm up out of the way. Then he lifts his left hand when the attendant removes the blanket.