The last two films by Damien Chazelle have both included ideas of dreams: Whiplash and La La Land; another favourite is Black Swan, directed by Darren Aronofsky. You could possibly explore the differences and similarities between such a theme in these films (or others, these are just suggestions); what makes these characters so willing to sacrifice things for their dream; in what ways dreams are presented differently in various films; the idealistic view of dreams vs realist depiction of them. It could also be titled something like ‘The Presentation of Dreams in Film’.
Nice suggestion. Movies, especially Hollywood movies, are in themselves the product of the dreams of the creators, hence 'The Dream Factory', so we could consider movies that address the escapist dream theme as dreams within dreams. It might also be worth noting that Aronofsky was influenced by another great dreamer - the Japanese anime director Satoshi Kon, whose 1997 film' Perfect Blue' heavily influenced Aronofsky's 'Black Swan'. – Amyus5 years ago