Character mistake: When Neal tells Rebecca about an Indian Idol and describes the idol to her, she tells him it's the Hindu Idol of Seeta, the goddess of wealth. Actually the idol is of Goddess Laxmi.
Continuity mistake: At the end of the episode, the Mercedes S class that is burning is not the same car that Castle drove previously in the episode, it's an older model one. Either it's a mistake or has to do something with the plot resolution, decide yourselves...
Visible crew/equipment: At about 30 minutes into the episode, right after Cal says: "if Jeffrey knows about priox, he's going to jail. But I'm gonna be damn sure before I send him there", you can see a hand in the top right corner of the screen.
Visible crew/equipment: At the end of the episode, when Alicia is listening to the audio recording on her laptop in bed, you can see the hand of a crewmember on the corner of the white cupboard at the left side of the screen. (00:42:45)
Visible crew/equipment: In the rec hall, when Kensi feigns sickness while posing as a cadet the gunman jumps off the stage, and as Kensi bends over the small rectangular bulge of her mic pack can be seen at her back. (00:30:25)
137 Sekunden - S1-E3
Factual error: When browsing for information about the crow deaths in the Ganwar Region of Somalia, the computer indicates that the CDC requested additional funding from DHS. The only problem with that is, DHS was formed in 2002, 11 years after the incident in Ganwar. (00:40:05)
Suggested correction: Although the Department of Homeland Security - commonly abbreviated as DHS - was not formed until 2002, in the later episode "Revelation Zero" it is indicated that DHS stands for an agency called Demographic and Health Services.
Ring Finger - S1-E10
Other mistake: When Jackie uses the hammer to smash her Ring Finger, if you watch carefully the prop hammer actually hits her middle finger instead. (00:24:30)
Continuity mistake: Towards the end of the motorbike scene, Matt performs a wheely and overtakes Echo. In the following shot Echo is in front of him again.
Continuity mistake: Tara is sitting at her desk and tells Max they will have sex the following night, and she teases him that she "Might even bring some props." Right as she says this line, the camera cuts. In the first shot, she has one pencil in each hand, but in the second shot, suddenly both pencils are in her left hand. The position of her hands changes between cuts as well.
Plot hole: Bonnie is the anchor for the other side and feels when supernatural beings die. How come she didn't know Katherine wasn't dead? Did she never think it was suspicious that she never felt Katherine's body after she died?
Suggested correction: Katherine died but didn't go to the other side. So she didn't need to go through Bonnie. She went to hell to Arcadius. Bonnie is not the anchor to hell, we don't know how going to hell works.
After everyone finally realises that Elena had been possessed by her Doppelgänger Predecessor, It is actually shown that Katherine were more or less dragged away from Bonnie before she could crossover to the Otherside. So we do have some idea as to how one ends up in Hell.
Suggested correction: Katherine was a human technically when she died.
Technically, she was supernatural because she was a doppelganger, so she should've gone through Bonnie.
And even she was a traveller.
Audio problem: When detective Bryant gets rough while interrogating the suspect of the shooting he tells him to sit down. When we cut to a different angle we hear him repeat the last few words of his sentence.
Continuity mistake: Jill writes Hank a goodbye letter which she hands to a friend to deliver. In the letter which Hank reads the next day, Jill states how beautiful Africa is and how Hank must visit. She wrote this before she left and had not seen Africa yet.
There Is No Normal Anymore - S1-E2
Continuity mistake: The beautiful blonde visitor takes a picture of herself on Tyler's phone. However, we get a perfect view of her as she concentrates to take the snap (looking very serious and studious, barely showing her teeth), but when we see the picture she is wearing a classic toothy smile right across her face. (00:23:00)
Factual error: In the banner for the exibition in France at the start, the French isn't right. It says "Opéra nationale" and "La morte de Marie Antoinette Des objets fabriqués de le temps de Marie Antoinette". It should be "Opera national" and "La mort de Marie Antoinette Des objets fabriqués à l'époque de Marie Antoinette" or "des objets fabriqués du temps de Marie Antoinette".
Continuity mistake: The assassin is running across the square with the poisonous needle in his left hand in several shots. But moments later, when tackled to the ground, it is pressured from his closed right hand.
'This Is America' or 'Fifty Bucks' - S1-E9
Continuity mistake: When Ray is talking to his son in the hallway outside of the detention room, his son has his arms out in front of him when the shot is from behind, but in the next shot facing him, his arms and body are in different positions.
Plot hole: The White Knight is knocked out by a bomb in his attack on the casino. When he regains consciousness, he fires one last crossbow shot, which he thinks destroys the casino. But who loaded and cocked the bow for that last shot? Crossbows don't reload themselves.
Factual error: At the beginning of the episode, Patrick Swayze is looking at photos of two Iraq veterans who have been murdered. He identifies one as a Marine Lance Corporal and the other as an Army PFC, but both pictures show men in U.S. Army uniforms. A bit later, his partner, who is supposed to be a Marine vet, refers to his decision not to "re-up," using the Army term for re-enlistment, rather than "ship over," as it's referred to in the Navy and Marines.
Continuity mistake: During the funeral, 2 is hit with a rock thrown by a young boy. In subsequent shots, the wound on his forehead changes size and configuration several times.