Who is Dennis Barlow from The Loved One and what is their importance?

Dennis Barlow is a twenty-eight year-old Englishman who has come to Los Angeles after writing a well-received book of poems while he was in a non-combatant posting with the British armed forces during World War II. Barlow is hired by a Hollywood studio to write a screenplay for a film on the life of the poet Percy Shelley, but he quickly becomes disillusioned by the tedium and lack of imagination in the studio system.