Thelonius acting really was terrible.
He started out fine. I read they shot this film in chronological order. As the film went on, his delivery became worse and worse. I know he didn't know much English and was not an actor. His intonation was so odd and it can't be blamed on the fact that he has a French accent. Also his rhythm was way off and he sounds very unnatural. He just rushed all the words together too fast a lot with no pauses. It can be blamed that he did not understand the words he was saying and was trying to act without knowing the meaning.
It is really obvious that he didn't know the meaning of his lines in English because he emphasizes the wrong word or words in the sentence. Instead of "Here's looking at YOU, kid" he just says "here's looking at you kid" with no pause -between you and kid--as if he never saw he movie. Especially when he is angry. Instead of "Have you been lying to us ALL this time?" he says "Have you BEEN lying to us all this TIME" "I REALLY don't want to see this terrible movie AGAIN" he says "I really don't WANT to SEE this terrible movie again" These are bad examples but it was very unnerving as the movie went on that his lines were being read without meaning. The intonation was all wrong! I could really hear it when he was supposed to be mad at the old man or Lauren. Like when she was calling Natalie from the phone booth he says "What did you call her for for?" He says "What DID you do CALL her for?" Instead of "Why did you tell her we are in Italy?" he says "Why did YOU tell her we ARE in Italy?" Often rushing the last part of the sentence when that was the part that needed emphasis. Not only that he uses vocabulary that a beginner in English would never use. As someone who learned English from the movies I don't think would ever say "I spent all week handicapping this race and you win on a HUNCH!" Hunch- really? That was in his vocabulary.
I loved the movie and thought he was cute and decent in it, but his ddelivery really started to get on my nerves. ANd MANY actors do not speak English as their first language yet can act in English getting the intonation correct.