If you're a writer and you're having trouble staying motivated, focused and you're being constantly interrupted by selfish people who don't take your writing seriously, then The Tenants is the novel (1971) and film (2005) for you.
If you want examples of two writers who take their writing extremely seriously, then read this book and watch the film. The novel is a page turner and the film, which is a great adaption of the novel, should be a cult classic for writers.
Here's the plot summary from IMDB:
In an abandoned tenement, an African-American militant writer and a Jewish novelist develop a friendship while struggling to complete their novels, but inner tension rises between the two.