None of the main characters speak for the first 21 minutes of the show, ironically titled "Unspoken".
The first words in the episode are "Speak. Say Something. Anything."
Neal McDonough (Grant Hamilton) appeared in the CSI: Crime Scene Investigation (2000) episode Sheltered (2013) (#13.18) in a different role.
Neal McDonough (Grant Hamilton) and Anna Belknap (Lindsay Monroe) both appeared in Medical Investigation (2004).