Singers turned Actors - The Best, The Worst

[floridaswamprat]

To honor the passing of Glen Campbell, we watched the only movie that I own with him in it - True Grit (1969). While Campbell was iconic as a singer, musician, and performer, he certainly did not convey those talents to the acting field. While his performance was cringe worthy at times, I do find the movie to be solid entertainment.

This got me thinking - who did successfully transition from a singer (or like entertainer) to a worthy actor? Who failed miserably?

Best: While there are obviously many who were successful, I will only offer one - Frank Sinatra. Perhaps he is "A-number-one, top of the list, King of the hill, A-number-one." But what are your thoughts?

Worst: Well, I mentioned Campbell, but I am not sure if he is the worst, but it was pretty bad.

NOTE: Do not include actors who turned singers (i.e. Travolta, etc.) That would be for a different discussion, I suppose.