It was common coin in Shakespeare's time to speak not only in double negations, but in double superlatives as well-:)
Mixed English Grammar Thread
n double superlatives
Wow,. good to know -
While I may scape,
I will preserve myself: and am bethought
To take the basest and most poorest shape,
That ever penury, in contempt of man,
Brought near to beast.
...or: This, the MOST UNKINDEST cut of all. (Hamlet Act II Scene I, if memory serves me correctly).