Emilio Estevez's boss at the St. Elmos bar is Blake Clark. You may know him as Farmer Fran in the Adam Sandler movies 'WATER BOY' and the homeless guy in the wedding scene in 'I NOW PRONOUNCE YOU CHUCK AND LARRY'.
Andie McDowell who plays kirby's long lost love may have been in 'Greystoke - the legend of Tarzan' before this but her voice was dubbed by Glenn Close for sounding too southern. In St Elmo's fire she is a wonderful addition.
Demi Moore's character, Jules, is the only main character whose last name is not revealed. The others are Alec Newbery, Leslie Hunter, Kirby Keger, Wendy Beamish, Billy Hixx, and Kevin Dolenz. According to the script for the film, the full name of Demi Moore's character is Julianna "Jules" Van Patten.
The character Felicia (Billy's wife) was played by Jenny Wright, who then went on to play Mae in "Near Dark". She is also well known for her role as the "lead groupie" in Alan Parker's "Pink Floyd: The Wall". She acts out the role first heard on the album of the same name. "Wanna take a baaaaath?". Jenny would also go on to star in another feature with Emilio Estevez. She starred as Jane Greathouse, a "madam" in "Young Guns 2".
Emilio Estevez, Ally Sheedy and Judd Nelson played together in "The Breakfast Club" in 1985. Emilio Estevez played the athlete "Andrew Clark", Ally Sheedy played the basket case "Allison Reynold" and Judd Nelson played the criminal "John Bender".
The 'hooker' that Andrew McCarthy's character is talking to is none other than Anna Marie Horsford from 'Ice Cube's Friday movies'. She can also be seen on the sitcom 'Amean' with Sherman Hemsley from 'The Jeffersons'.
Whilst still courting each other, Emilio Estevez & Demi Moore both starred in "Wisdom" which was an 'Estevez' vehicle as it was Emilio's debut as a Director. This movie was a modern day 'Bonnie & Clyde', but without all the killings. Emilio starred in this film as a 23 year old who had a few drinks with his buddies one night, which turned into a silly stealing car scenario. His arrest then followed with a botch in his otherwise clean record. Emilio and Demi played lovers in this film.