There are lots of clever things in it that you may not realise if you know nothing about Shakespeare.
For example in Elizabethan times there were many different ways to spell words, and people did not always use the same spelling all the time for a certain word.
There are only 6 surviving signatures for Shakespeare, but he seems to spell it differently in each signature.
So in the opening of the film you see him practising his signature and when he gets it "wrong" the screws up the paper and throws it in the bin.
This is a sort of "in joke" about the misspelling of his name in his own signatures.
Also in the same scene the camera pans across the room and you see a mug on the shelf with "Present from Stratford upon Avon" on it.
Another "in joke" because of course Stratford was not famous then, it only became famous as his fame spread and tourists started to visit Stratford in modern times to buy souvenirs.
Now if you go to Stratford there are these mugs for sale all over the place.
So there are lots of clever things like this in the film and it does pay to watch it carefully.
It is also a cracking love story, thriller, and light comedy with many great performances.