I went to see Darkest Hour the other day.
https://www.youtube.com/watch?v=LtJ60u7SUSwIts honestly very enjoyable, whilst there are some bits that are not historically accurate, you can forgive them because they seem very Churchillian, and what we know of the man, his personality, his mindset, it really wouldn't surprise me if he did bits like it.
Gary Oldman does a very good job as Churchill (to the point that in filming he made himself rather ill with all the real cigars he was smoking for the scenes), and gets the man's mannerisms, and most difficultly, his voice and way of speaking pretty spot on.
It shows Churchill's difficulties with his opponents in the War Cabinet, his initially rather fraught relationship with the King, mentions some of the honestly
very bad ideas that Churchill had, so its not trying to even present him as Saint Churchill of England. Its a good solid representation of the man. I thought that Albert Finney had done an amazing Churchill in the HBO TV movie The Gathering Storm, but Mr Oldman's take on him is superb too.