The Defence of Monaco.

Film Grace of Monaco is in no way the disaster you've been told it is. It's just that it tosses out historical accuracy in favour of pure melodrama, has the aesthetics of a perfume commercial and is attempting to recreate a particular tone of film typified by the late fifties technicolour cinemascope of 20th Century Fox. Brad Stevens offers a lengthier defence at Sight & Sound:

"All the film’s motifs and concerns can be found in its exemplary opening shot, which seems to begin with the camera retreating down a road. This is soon revealed to be an image projected on a screen in a Hollywood studio where Grace Kelly is shooting High Society (1956). As actors and technicians applaud, Grace leaves the set, Dahan’s camera following her from behind. Only after she has entered her dressing room and positioned herself before a mirror do we finally catch a glimpse of Grace’s face, and we see it only via a reflection. Grace’s aristocratic power and control are emphasised by the way she hands some flowers she has been given to an assistant, then begins removing her coat, which is immediately grabbed by another assistant."

It's worth noting I really enjoyed both Diana and W.E. for similar reasons.