This episode is a riff on John McTiernan's Die Hard (1988). As an homage to the director, the van used to gain access into SD-6 is labeled as an air conditioner repair company named "McTiernan Air Conditioning''.
First appearance of Dr. Judy Barnett, played by Patricia Wettig. Wettig is the wife of Ken Olin (executive producer, developer, and director of Alias (2001)).
Sydney suggests she and Vaughn should go see the L.A. Kings who "are in town next week" are playing the New York Islanders. This episode was aired January 20th, 2002, and the Kings actually played the Islanders in LA one night before this episode aired (the Islanders won 3-2).
Originally, "The Box" was to be a single episode, but it was realized that it was going to be too long for one episode so extra material was added to fill out two episodes. Something similar would later happen with Special Guest Star Quentin Tarantino's Kill Bill movies.