The reason I'm mentioning it here is because in a scene towards the very end of the movie Bob whispers something into the ear of Charlotte before they part. (I don't think I'm ruining the film for you by telling you this... but you might want to watch the film first before reading further; at the very least it will give you a context!). Thanks to the wonders of YouTube (and my new-found ability to post YouTube videos...) you can view the scene below:
We don't get to hear what Bob actually says, apart from he ends by saying "...OK?", to which Charlotte respondes "OK". Of course, you're not supposed to be able to hear what he whispers (the DVD subtitles say "inaudible", I tried it), but I was interested to know whether a line was scripted for the scene, or whether Bill Murray improvised a line, or whether he just mumbled a few meaningless words. And it seems I'm not alone. For example, one of the reviews I read (at felixsalmon.com) was followed by many comments relating to what Bob actually says (the other main concern seems to be where can you get hold of the cherry blossoms like those that Charlotte hangs in her hotel room). What's interesting, is that there are a range of opinions regarding what Bob says.
"You have changed me irreversibly... [inaudible] ...Stay here and I will be back for you in a week, OK?"
"I was ready... [inaudible] ...on the way back, you should tell him the truth, OK?"
"I'll always remember the past few days with you... don't part mad, tell him the truth, OK?"
"You want to have a better performance? Go up there and tell him you love him right now."
"I love you, and everything you did. Go back there and tell him to try, OK?"
"Promise me... [inaudible] ... on the flight back, tell him the truth, OK?"
So I'm not any closer to an answer! I have just listened again to the scene and to me it sounds as though he begins with "Promise me..." and ends with "...and you tell him that you love him, OK?".
Some of those speculating on Bob's words even put forward some evidence in order to support their claims. For example, one points us to this website, that has scripts for hundreds of films including Lost in Translation. But when I looked just now, Lost in Translation wasn't there (it goes from Lost Horizons to Lost Souls)! Another points to a different website, where you can play the clip either with 'normal sound' or with 'enhanced sound', claiming that when you listen with the enhanced sound Bob clearly says "I love you, and everything you did. Go back there and tell him to try, OK?". Finally, one person points us back to YouTube, saying that if you search for "Lost in Translation whisper", you will find the answer. Well, folks, I did that. And, because I can, I have posted it here. Are you ready for the answer?
No way! I listened to it that time, and was convinced he ended by saying something like "... and you tell him the truth, OK?". It definitely was not "...but I won't let it come between us, OK?".
So I think we are left with not knowing. And not knowing is probably better than knowing. Because knowing is bound to be a disappointment. At least this way, whatever Bob whispers into Charlotte's ear can be what we want it to be, and from what we've seen (and heard) it seems that's exactly what people are doing. The idea is that you aren't told what is whispered. It's up to you to decide for yourself. I'll leave you with the words of one of the comments on felixsalmon.com which ring very true:
"The script isn't punishing you by not letting you hear the whisper, it's a reward. That whisper can be whatever you think it is. Whether you're a romantic, a cynic, or somewhere in between, the unintelligible whisper provides a perfect ending. I know exactly what he said, but I'm not going to tell you. You have to figure it out for yourself (hint: turning up the volume will not help)."So we'll leave it at that. It is what you want it to be. I'm happy with that.
(But if you do have any inside information regarding what Bob actually does say...)