The doctor listens to Hayden's heart over the patient's right shoulder then in the next shot his stethoscope is on the left side of the patient's chest.
There is supposedly one band aboard the ship, but in different scenes there is a right-handed as well as a left-handed bass player visible.
When Columbo goes to the pool to check the filter, there is a lady in an orange bathing suit sitting next to an older man on the edge of the pool, and there is a woman with a multi-colored swim cap in the water. The shot cuts to the left-rear angle as Columbo climbs over the railing to get next to the pool, and the two women and man have disappeared. The shot changes to Columbo pulling up the filter from the water, and the 3 people are back again.
Also, as Columbo starts climbing over the railing, his coat is hanging on his arm as he grabs the railing with both hands. When the view changes, Columbo is holding the coat in his hand, and he never touches the railing with his hands as he crosses over.
Also, as Columbo starts climbing over the railing, his coat is hanging on his arm as he grabs the railing with both hands. When the view changes, Columbo is holding the coat in his hand, and he never touches the railing with his hands as he crosses over.
When Columbo is called into Miss Wells' cabin after she is murdered, there is now a bullet hole on the lower left side of her back, even though there was not one immediately after the shooting.
All in the same sequence, Columbo is on the shuffle board court with Hayden Danziger (no tie), goes to the sick bay (has a tie on), goes up and talks to Mrs. Danziger (no tie).
When the murder weapon is found from the laundry it is identified by the Captain and Columbo as a British Weatherby revolver. Also the receipt for the purchase of the gun, which obviously would have its make, was observed by both parties. However Weatherby Inc is an American company which makes shotguns, and rifles, but does not make handguns. But a British gun manufacturer, Webley, do make handguns.
No bruise or mark ever shows on Rosanna Wells' (Poupée Bocar) face despite her having been punched hard enough with a man's clenched fist to knock her down. Even with makeup, such a contusion would show.
Pillows cannot act as silencers. This is a convenient Hollywood myth.
The fake heart attack caused by amyl nitrite is a major plot point. However, amyl nitrite is used to counteract a heart attack. It expands blood vessels, resulting in lowering of the blood pressure. So it could not be used to simulate a heart attack. That's also why the ads for erectile dysfunction remedies warn not to use if the patient is taking nitrites.
Also it comes in glass vials covered with gauze, as Colombo found in the pool filter. It is a liquid, not "crystals."
When the nurse checks Danziger's blood pressure, the cuff does not inflate.
When Columbo is timing himself to see how long it takes to reach Miss Wells' cabin, he asks a crewman if there is another way to her cabin. The crewman fails to mention the crew stairway, which he surely would have known about, even more so as he is standing right by it. However, Columbo was asking about a shorter route from the International Lounge, not the sick bay, so the crew member answered truthfully and knowingly.
Columbo uses graphite dust to reveal the fingerprints and palm print in a sickbay glove. He turns the glove inside out to put the prints on the outside. Normally when this type of glove is worn and then removed, the glove is turned inside out, but since Hayden was trying to frame Lloyd, he would have been careful to either remove the gloves so the did not turn inside out or to turn them back so the powder burns would be clearly visible, thus once again Columbo knew what he was doing.
When Columbo finds the capsules in the pool filter, he is being closely watched by culprit Hayden Danziger (Robert Vaughn), who used the capsules in his murder scheme to fake a cardiac arrest in the pool. Knowing that Columbo actually suspected him of murder all along, why would Hayden then fall for Columbo's entrapment ruse that the Lieutenant only wants evidence to convict Lloyd Harrington? The murderer would know he is being tricked.
When Columbo is talking to the doctor, he asks if there were any bruises on Miss Wells' body and is told, "No bruises". But Danziger (Robert Vaughn) punched her in the face in her cabin just a few hours earlier, knocking her down. It's unlikely this would not have left a bruise.
When Hayden Danziger kills Miss Wells and disposes of the gun in the laundry room, he is locking and unlocking doors; however, there clearly is no key in his hand, and he is just pretending to turn one.
When Columbo and Danziger are playing shuffleboard, after they leave the game, one older man plays a bit and then leaves. He runs down the steps but stops when he thinks he is off-camera. Then he looks back at where the camera is and quickly continues exiting the scene.
When Hayden fires the revolver into the mattress, there is NO muzzle blast from the revolver, no bullet hole is created in the mattress, and no powder burns are left on the mattress.
Lloyd Harrington can be seen sitting at the piano during the magician's act. This comes right after the Captain had confined him to his quarters for the murder of singer Rosanna Wells.
Amyl nitrate i.e. smelling salts do come in breakable capsule form and depending on the heart condition of the person could produce the effect of a heart attack.
While Rosanna Wells is singing the song Volare and hands out the microphone to a member of audience, it does not have any effect on the sound of her voice; it is the same with or without the microphone.
When the band is playing during Miss Well's break, the band's hand movements on the instruments do not match the music. This is very apparent by watching the bass players hand movements compared to the music.
The murder weapon is determined to be a .38 caliber revolver, yet no one bothers to tell Columbo that the magician performing on-board has what appears to be a genuine .38 revolver which is later shown being used in his act.
During the return trip back from Miss Wells' cabin, there is a conveniently placed room service cart and tray in the stairwell that Danziger picks up to obscure his face from another person coming down the stairway. However, the stairway is a half-story stairway that utilizes a landing to change the stairway's direction to maintain a small stairwell footprint. Not only is there no reason for the cart to have been left unattended on a stairway, which is not allowed on a ship in case the stairway must be used during an evacuation, there are only stairs on both sides of the landing. This means that the cart would have had to have been drug either up or down one set of stairs.
The killer takes great effort to frame Lloyd for Wells' murder. However, he makes no effort to determine if Lloyd had an alibi, or take steps to lure Lloyd away so Lloyd wouldn't have an alibi. If Lloyd hadn't lacked an alibi, the killer's entire plan would have fallen apart.
When Danziger put on surgical gloves and fired a gun to replicate gunshot residue on the outside he carefully removed them to ensure they were not inside out. However by pushing the gloves into the fire-hose with his bare hands he would have left his prints on the outside rendering Columbo's 'gloves inside out' trick to identify the user's (Danziger's) fingerprints and palm prints potentially unnecessary. Columbo never thought to first check the outside of the gloves for prints.
One of Columbo's key pieces of evidence is that Danziger's heart rate and blood pressure were elevated when the nurse checked his vitals shortly after the murder had occurred. This was supposedly the result of Danziger having run down to Miss Wells' cabin and running back.
However, an alternate explanation that Danziger could use to explain this is that the nurse woke him from a dead sleep, startling him. Thus, the increase in his pulse rate and blood pressure was due to having been startled awake and not from physical exertion.
There is a shadow on Hayden Danziger's back when he planting the gun receipt in Lloyd Harrington's cabin.
Danziger suffers from an apparent heart attack, yet Mrs. Danziger is never once shown visiting her husband in the sick bay.
The nurse (twice) and the doctor both put the stethoscope in their ears the wrong way around: to be able to hear the sounds travelling from the membrane on the chest or limb up to the earpiece and into one's ear canals, the ear pieces must be facing forward, not backwards as often depicted on screen.
The ship's medical staff do not appear to know what they are doing. When the doctor is listening to Hayden's heart, he holds his stethoscope over his chest instead of laying it on the chest, and twice the nurse takes Hayden's blood pressure by putting the cuff around his elbow, which would give an invalid reading.
Columbo mishandles key pieces of evidence during the case. He loosely keeps the bullet from the murder in his pocket. Because of this it's subject to being damaged and he cannot prove a chain of evidence and it would not be admissible as evidence. When he is handling the surgical gloves and checking them for fingerprints he handles them with his bare hands, which would also make them useless as evidence.
While his name is listed in the credits as "Danziger", Columbo always talks and refers to him as "Danzinger". The crew always refers to him as Danziger.