She sees enormous potential under the cynical veneer, so to get close to him she calls herself Mary and pretends to be blind with the help of Dan's colleague, Chick (Hoagy Carmicheal) and her aunt, Ms. Willey (Ethel Barrymore).
Not only does Cathy help Dan compose again, but she creates a contest that can give him enough money to reverse his blindness. But once he has his vision back, he forgets about "Mary" and becomes enamored with Cathy Mallory, the rich socialite.
Night Song shows the following tropes:
- At the Opera Tonight: The film climaxes when Dans composition is played by Artur Rubinstein, and Dan begins to remember his times with Mary and the big role she played in changing his life.
- Blind Musician: Dan's a talented pianist who loves the classics and was a big shot composer before the war, but a freak accident after the war that blinded him.
- Cool Old Lady: Cathys aunt reads pulp fiction detective stories and is devilishly good at cards.
- Dark and Troubled Past: Dan describes his life growing up as a homeless kid to show Cathy how sheltered she is and why her playing isnt the best.
- Deadpan Snarker: Ms. Willey gets all the best lines.
- Disabled Love Interest: Dan is Cathy's talented blind love interest.
- Dream-Crushing Handicap: Although still able to play piano, Dans accident was quite recent, so his depression stops him from composing music.
- The Eeyore: Dans blindness was only a year and half ago, so he does have a reason to be such a downer, but he can be a little hard to handle at times with his constant negativity and rudeness.
- Heterosexual Life-Partners: Chick and Dan. Dan relies on Chick to be his eyes whenever he goes outside.
- Jerk with a Heart of Gold: Dan for the most part.
- Maiden Aunt: Willey has never married though she does hint at being hurt by love.
- Rich Boredom: Willey thinks that Cathy taking on the project of helping Dan stems out of this.
- Secretly Wealthy: Cathy and her aunt rent out a rundown apartment to hide the fact that they are rich from Dan. If they hadn't hid this, he wouldn't have given them the time of day.
- Secret Test of Character: Cathy tests Dan by dating him as herself to see if he'll return to Mary.
- Two-Person Love Triangle: Cathy Mallory loves Dan who still has feelings for Mary Willey, whos really just Cathy when Dan couldnt see.