Continuity mistake: When Barney is at the apartment in his Top Gun costume, the position his helmet is in on the coffee table changes between shots. Sometimes the front of the helmet faces the camera, at other times it is sideways. (00:06:00)
Continuity mistake: When explaining why he has 2 costumes every year, the way Barney holds his drink changes instantly. (00:12:00)
Continuity mistake: At dinner, Robin starts eating the ice cream sundae and knocks the cherry off the top. In the next scene, when she passes the sundae to Mike, the cherry is back neatly on top and the sundae looks untouched. (00:12:50 - 00:13:30)
Continuity mistake: When the Hula girl realises the penguin is Barney she holds her hands out and walks off. Camera cuts and her hands are on her hips. (00:17:30)
Continuity mistake: Robin says in this episode that she never played team sports and was always a loner. However in a later episode, (The Prom episode) she mentions she missed her prom due to field hockey nationals.
Other mistake: In the credits, Jeremy Gabriel (Robin's new 'boyfriend') is shown as "Mark" but it is "Mike" throughout the episode.
Continuity mistake: Robin says that she doesn't like team sports, and so she only played tennis in high school. However, throughout the show, Robin often talks about playing hockey during school, which is a team sport.
Continuity mistake: At the bar, when Robin is telling the gang about Mike, Marshall's beer moves from in his hand to on the table between shots. Also, the amount of beer in the glass changes frequently depending on the camera angle.
Matchmaker - S1-E7
Continuity mistake: In the opening scene at the bar, when Ted and Barney are discussing the idea of going to visit a Matchmaker, Ted's beer glass suddenly goes from being about a quarter full, to being nearly three-quarters full. (00:02:20)
Matchmaker - S1-E7
Continuity mistake: At the Matchmaker's office, when Barney is saying he just wants someone to hold, Ellen is seen putting her pencil down on the desk but in the next shot it is in her hand again. (00:03:50)
Matchmaker - S1-E7
Continuity mistake: When Marshall comes out of his room with the book about the Roswell Incident, he's holding the cover and first pages bent under the book, next shot he's just holding them normally, then they're bent again. (00:14:30)
Matchmaker - S1-E7
Continuity mistake: In the final scene at the Matchmaker's office, the tub of Haagen Daaz on the desk turns around between shots. Sometimes the brand name is visible, but in other shots the logo is facing away from the camera. (00:20:00)
Continuity mistake: When Lily and Marshall are talking in the kitchen, we see Lily put down the recipe card to the left of the jar of mayonnaise. The shot changes and the card is now to the right of the jar. (00:06:25)
Continuity mistake: When Lily is making the layered salad, in some shots the layers are defined, but in others there is much more mayonnaise running between the layers. (00:07:30)
Continuity mistake: When Lily drops the potato chips on top of the 'salad', we can see a few chips sticking up beyond the top of the bowl. The shot changes and now the chips are laid flat, with none sticking up over the top. (00:07:40)
Continuity mistake: When Marshall and Lily are talking in the jail cell they are holding hands, then the shot changes and both have their hands in their laps. (00:17:35)
Chosen answer: She was finally shown at the very end of the last episode of season 8, continuing into season 9. The actor's name is Cristin Milioti: http://www.imdb.com/name/nm2129662/.
Knever