- Alternative Character Interpretation: Theresa. She is either...
- A Stalker with a Crush, who fixates on Garret after discovering his and Catherine's letter, and becomes obsessed with finding him. She goes as far as to order an analysis of the type of the paper used by Garret, before tracking down his home and lying about her intentions.
- She is alternatively a person whose intentions are pure and honest, and she simply goes about it the wrong way.
- Alternatively, her fixation on the letters one of which wasn't even written by Garret and she never noticed, can be chalked up to Loving a Shadow.
- Retroactive Recognition: The little girl Garrett saves from the sinking boat in the climax (at the cost of his own life) is a wee version of Hayden Panettiere.
- Catherine's brother Hank is played by Tom Aldredge, who went on to play Hugh DeAngelis in The Sopranos.
- Spiritual Antithesis: To Sleepless in Seattle. They bear many plot similarities, but while Sleepless is a Rom Com where the woman stalking a man she has never met is portrayed as comically obsessive, Bottle's protagonists are a doomed romance that ends tragically.
- Strangled by the Red String: That this story was meant to be a tragic star-crossed romance didn't help Kevin Costner overcome his reputation for bland, wooden acting.
YMMV / Message in a Bottle