Character mistake: When Gina tries to set up Rosa on a date, Rosa mentions the last person Gina set her up with (Justin) was a dork who rode a Yamaha motorcycle. She says "he might as well have picked me up in a station wagon." Rosa's bike is a Yamaha R1.
Character mistake: As Reddington sets up the blood transfer between himself and Ressler he inserts the intravenous line in Ressler's arm first and then in his own arm. This way the remaining air inside the line gets into the recipient's body and could very well kill him. Judging the expert way he handles the set up he should know to first insert the IV in his own arm, let the line fill with blood and then insert the IV in Ressler's arm.
Suggested correction: That amount of air would probably not cause any problem. It actually takes quite a lot of air to cause any issue.
The Committee on Human Rights - S5-E7
Character mistake: Renee refers to Indiana University as U of I. It should be IU. U of I would only refer to the University of Illinois, one of their main rivals. (00:31:00 - 00:33:00)
Episode #1.2 - S1-E2
Character mistake: In the incident room Danny's height is written as 4ft 8inches / 112 cm. 4'8" is 142cm. (00:06:48)