As "Forgetting Sarah Marshall" proved, he's only good in small doses; as "Get Him to the Greek" proved, he's downright grating in large ones.
Taking over Dudley Moore's iconic, Oscar-nominated title role, Brand seems not to have undergone any great stretch to portray a rich, spoiled, drunken, promiscuous man-child. We're asked to laugh at his careless, intoxicated shenanigans he's wearing Abe Lincoln's actual suit! He dressed as a giant gummy bear! He's got a Batmobile and a "Back to the Future" DeLorean! but the script has not a single effective joke to affix to those supposedly riotous situations.
I don't know if it's Brand or the character as scripted I'm guessing the former, based on his previous performances and interviews but he won't shut up, as if he'll eventually produce a gem if he just keeps yapping. He doesn't (also see: Robin Williams). He actually handles some of the third-act drama well, yet director Jason Winer (TV's "Modern Family") force-feeds the material, diluting any emotional power.
Mumblecore queen Greta Gerwig ("Greenberg") is clearly out of her comfort zone, exhibiting an awkwardness in the Liza Minnelli role. I felt palpable embarrassment for both Helen Mirren and Jennifer Garner for some of the things they're asked to do.
Although I've seen the 1981 original "Arthur" probably half a dozen times, it holds no special place in my heart, so the idea of a remake isn't sacrilege to me, but this one seems more needless than most. Rod Lott