Danno pays a visit to the doctor due to a tear in his ACL and has to use a cane to get around. This was written into the script after actor Scott Caan actually injured his knee during a stunt.
First time the team refers to itself as 5-0. Previously referred to as the Governor's Taskforce.
First appearances of Steve's sister Mary Ann along with Lt. Rollins.
First episode to feature Michelle Borth as Catherine Rollins.
Jack McGarrett's marker has his death as September 20, 2010. The air date for the pilot of the series.