In an effort to boost ratings, Robert Downey Jr. was hired to play Ally's love interest at the start of season four. The ratings increased and David E. Kelley began planning to have that season end with the wedding between Ally and Robert Downey Jr.'s character. However, before production on the season finale could begin, Downey was arrested on a drug-related charge. Despite objections from David E. Kelley, Fox fired Downey from the show and forced Kelley to have to rewrite a brand new season finale episode that removed Larry Paul character from the series and rewrite and re-shoot a new ending to the previous episode so as to remove all references to the aborted wedding storyline. Ironically, the episode's title remained "The Wedding".
Ling Woo (Lucy Liu) wasn't originally intended to be a regular, but David E. Kelley liked her so much as a guest star, he and the writer decided to reveal that she has a law degree and join the firm after a few episodes, giving her a reason to be there.