Lots of people have been saying that Josh Hartnett should had played a young Tommy Lee Jones in Men in Black 3 instead of Josh Brolin. Now I admit I am a nerd and making an ant hill into a mole hill. Will Smith's J travels to 1969 to find a young K. Tommy Lee Jones is now 66 and you can suppose that K is 66. In 1969, Tommy was 23. Josh Brolin is currently 44 but this is a movie so I suppose K is not 23 in the movie.
I think Josh Hartnett looks more like Tommy Lee Jones. Hartnett is currently 34, not exactly the age Tommy was in 1969 either but it is Hollywood. Tommy Lee Jones is 6 feet tall and Will Smith is 6'2". But Josh Brolin is 5'10 1/2"--a bit shorter than Tommy. And Josh Hartnett is way taller than Will Smith at 6'3" so maybe that would had been an issue to. Anyway, this is as mute as the Angela Bassett as Storm in X-Men debate.