In HIMYM, there's a continual reference to the movie Departed in the dialogue between Ted and Marshall, which goes like: "-Are you a cop? -I'm not a cop." You can watch the scene here, which is from ...
It's in season 8 episode 3 of How I Met Your Mother at 8:22min. I found it on youtube too. "Barney!!!" "Icksnay on the ealray amenay!" "Mr and Mrs Erikson?" "Youuu son of a... itchbay!" The ...