George Burns won his Oscar from his first Oscar nomination for portraying Al Lewis in The Sunshine Boys.
I suppose with a rather broad definition of one note one could describe Burns's performance as such, but that would be one note of dead pan brilliance. From his first moment on screen to his last Burns is hilarious in the role, but just how much he downplays his entire performance. There is not a single visible moment in which you can spot Burns trying to go for a laugh as Al Lewis, yet that is all that Burns really is doing for almost his entire performance. This is a completely spot on dead pan work from Burns that it very very difficult to pull off effectively, after all you don't ever act out for you laughs you underplay for them, but Burns is a master of it here.
This approach is fitting for Al Lewis who is a rather unassuming old man who just likes to relax at his daughter's home, and spend time with his grandchildren, and really is the polar opposite of his former frantic comedy partner Willie. Their scenes together are the highlight of the film, as well as the only time I really feel that Matthau's performance and the character of Willie really work. Their dynamic is terrific as the constantly upset in some way Willie is always ready to argue at the slightest disagreement and Matthau really plays up every scene with all sorts of yelling and hand gestures, whereas Al is always calm, and Burns is absolutely quiet and barely moves.
Where Matthau's old man routine gets old in all of the other scenes, they work here because of Burns to basically make the punchline to every set up by giving his simple response to every one of Matthau's over the top action. I will admit Burns absolutely steals every scene, and pretty much just uses Matthau's performance to his own end, since every time I laughed at any of these scenes it was due to Burns not Matthau. Burns knows exactly how to play off of Matthau so really he always gets the last laugh. Burns is just on the entire time he is on screen and he never has a wrong moment during his entire performance, it is deadpan comedy gold from beginning to end.
George Burns is really just perfect in the role as the aged vaudevillian. I should also say that it does not matter whether he is Matthau or not, he is equally hilarious with Richard Benjamin as Willie's nephew and agent as he is with Matthau. Everything about Al Lewis is portrayed brilliantly by Burns rather it is his old aged memory lapses, to his actual on stage performance which although is still dead pan Burns brilliantly adds just a little more energy to the proceedings showing the difference between his off stage and on stage personalities. This difference is slight and subtle but Burns could not handle it better. Burns's act here never gets old, and every moment he has he makes as enjoyable and entertaining as he possibly can.
I will say that the more dramatic moments in his performance which come near the end are similarly well handled, even if they are short. There are two scenes in near the end of the film where he worries about Willie's health. Burns still stays consistent to his portrayal of Al as a quiet and simple man, but he does effectively convey that although Al and Willie constantly fight he does love the big guy after all. Burns again makes it simple but a genuine care he shows Al has for Willie, and it works extremely well for the end of the film. This is not the main facet of his performance, the main facet of his performance is just being funny in his brilliant deadpan manner, but it is just another part of this great characterization by Burns.