Main Theme
"Cherchez la femme, Cherchez la femme, Dans la nuit, Dans la nuit."
Translation: Look for the woman, Look for the woman, In the night, In the night.
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Season 1

106 Mother
A terrorist speaks Korean in the teaser.

109 Gray
Hardin's assistant speaks to Michael in Czech when he lets him into the building where the auction for the directory takes place, in Prague.
Hardin's assistant: "Zbrane!"
Michael: "Kdyz Benko je tady, tak ne."
Hardin's assistant: "On nic nema. Vsechno je v poradku. Chcete videt ten seznam nebo ne?"
Translation:
Hardin's assistant: "Weapons!"
Michael: "Not if Benko's here."
Hardin's assistant: "He's disarmed, too. Everything's secure. Do you still want to see the list, or not?"


112 Innocent
A terrorist is praying in Romanian.
Kassar: "Celui ce paseste in ceruri de mila proroceste al doilea mergator inaintea venirii judecatii lui Isus Cristos sfintului daruieste si pe noi pacatosii ne miluieste."
Translation: For the one going to heaven, second prophet, before the coming of the judgment of Jesus Christ the saint, give your charity and bless us, the sinful.

121 Brainwash
During the mission when Nikita snaps and almost shoots the Chinese prime-minister, Michael tell her no in French.
Michael: Nikita, non!


Season 2

201 Hard Landing
Michael is in a bar of some sort owned by Sherrin. He orders cha (aka tea). He speaks in Cantonese to another man, before killing him, and captures Sherrin.

207 Half Life
Whenever Rene Dion says Michael's name, it's Michel, the French version.
When Michael enters Rene's quarters, he tells him to stop in French
Michael: Rene, arrete.
Rene also sings a French song to Michael.
"Les bourgois c'est comme des cochons
Plus ca devient vieus, plus ca devient con."
Translation: The rich people are like pigs, the older they are, the dumber they get.

208 Darkness Visible
(See the clip here)
sign language being used. Sign Language
PETER: "Are you cold?"
SASHA: "Yes"

219 Last Night
The father asks his daughter something in Albanian, she shakes her head.


Season 3

302 Someone Else's Shadow
Prisoners being dragged in are speaking a foreign language.
When Madeleine interrogates them in the White Room, they also speak a foreign language and Madeleine answers in the same language. A viewer Bob Scheurle says it's Armenian and that the dialog is:
Man: My men will kill you. They will find you.
Madeline: Ov ghergetz kezi?
Translation: "Who sent you?"

The post office scene, when Michael goes in to set up the scene before Vacek's man arrive to get Elena's letter. The dialog is in Portuguese:
Clerk: Ola! (Hi)
Michael: Colabora e tudo correra bem. (Cooperate and everything will be fine)
Clerk: O que? (Or what?)

303 Opening Night Jitters
Mick: Unlike you, doll, my contract with Section is a bit more tenuous, to say the least. I mean, they use me for my ability to move freely in the world. The French call it "savoir faire".

304 Gates of Hell
During the mission when a man shoots his own son (and it's a Section operative, in fact, who is disguised as the father), hostiles speak a foreign language.

313 Beyond The Pale
Nikita and Michael talk to the truck driver in French during their escape.
Nikita: Merci. (Thanks)
Michael: Merci beaucoup. (Thanks a lot)

315 Hand to Hand
Cat: (yells something at Nikita in Russian)


Season 4

401 Getting Out of Reverse
During the mission that takes place at the Kazakhstan Embassy in Dushanbe, Tajikistan, a guard speaks some language that could be Russian. Later, during the same mission, other soldiers are also speaking Russian.
A gold Mercedes taxi pulls up outside the Kazakhstan Embassy. It pauses by a guard. Nikita drops from the underside of the Mercedes and goes down a manhole cover conveniently located in the driveway. The guard is speaking, I think in Russian? Then he conveniently switches to English when we are done watching Nikita.
Nikita climbs up and removes clothes now has on what looks like an army green military uniform with a skirt, black shoes, tie. She enters a room where several soldiers are talking, I think in Russian. She takes out a long narrow scope that allows her to see around the corner and then enters calmly, and kicks the crap out of them. She steps over the bodies and proceeds into another room where the captured operative is restrained in a glass cell.

407 Sympathy for the Devil
In the scene where Michael follows Willie, Operations' former camp friend from Vietnam. Some guy talks to Michael in Vietnamese and Michael replys the same way.

414 Line in the Sand   Listen to it
During the scene in the van with Nikita, Michael, Madeleine, and Operations, having just left Section before George arrived, and trying to find the Cardinal, Michael, Nikita, and Madeleine speak foreign languages with their exterior contacts.

416 Catch a Falling Star
Michael: Spassiva. (translation: "thank you") Mailman: Pajalsta. (approximate translation: "you're welcome") Michael catches one of the Black Storm guys by saying thank you in Russian and the guy answers in Russian too.

422 Four Light Years Farther
When Michael is parked in front of a bank waiting for Nikita, a woman in a uniform tells him in German that he cannot park there. Approximate transcription of what she says: Woman in uniform: Sie kennen nicht hier ansitzen.


Season 5

501 Deja Vu All Over Again
A prisoner being interrogated speaks Russian.

503 In Through The Out Door
Nikita speaks French to the caretaker at Adrian's rest house.
Caretaker: Bonjour. (hello) Can I help you?
Nikita: Uh... bonjour. My... my name's Nikita.
After the caretaker closes the door:
Nikita: You won't call the police. You'll answer my questions. Vous comprenez? (do you understand?)

508 A Time for Every Purpose
While Walter tries to convince Jason to help him survive Myra, WALTER: So, you think you’re smart just taking care for numero uno? "numero uno" - number one in Italian.