Yes, He Caine
It is not really a good movie. In the beginning you cannot help but thinking of "Best Sellers" as another version of that old-guy-meets-ambitious-young-woman-narrative so popular these days (and hardly ever working out) as in "The Apprentice": dealing with all those clichées you might have expected including a very predictable ending.
But then there is Michael Caine playing that grumpy old man hiding from the world. A once successful writer, he lives alone now with his cat in a completely run down house filling his days with drinking and smoking. When the struggling heiress of a publishing house tries to get him back to publish another book - and going on a book tour!! With her!) you expect a developing relationship between those two and, of course, a best selling book on the way.
You actually have to wait quite some time for this turn. And Caine seems to enjoy disappointing our expectations. So when he finally kind of gives in - we are touched even though we never went with the storyline.
Michael Caine still makes a movie work. Especially when he is not really the leading character as in "Hannah And Her Sisters" and my alltime favorite "Cyder House Rules".
So watch "Best Sellers" anyway - on youttube.com, for instance.