Marsha Thomason (Diana) was really pregnant while filming during this season.
James McCaffrey plays a member of the NYFD in this episode and he played a deceased member of the NYFD in the series Rescue Me
Molly Price played a cop on Third Watch and The Shield.
The NYPD officer talking down Moz on the building ledge also played a police officer for the NYPD in the TV series Third Watch.