B.J. Novak wanted Amy Adams to reprise her role as Katy in this episode, but Adams couldn't due to scheduling conflicts.
The "Threat Level Midnight" idea was introduced in The Client (2005), where the office discovers Michael Scott's screenplay in his desk while he's out and stage a reading of it in his absence. Paul Lieberstein wrote "The Client." He, the other writers, and Carell in particular wanted to return to the film idea and present it inside of a regular episode. An early plan to simply show the uninterrupted film as a special episode was nixed. When Carell's time on the show was near the end, the idea was brought up and Lieberstein assigned it to B.J. Novak to write.
Steve Carell (Michael Scott/Michael Scarn) actually used to play hockey in high school.
One of a handful of episodes in which the cold open is directly related to the rest of the plot. Others are: Halloween (2005); Christmas Party (2005); The Injury (2006); The Return (2007); Secret Santa (2009); Andy's Play (2010).
The theme of "Threat Level Midnight" is the main theme from the "Bourne" movies