It is mentioned that Jimmy is now a widower and single father, but never actually stated what happened to his wife, Breena.
In interviews Brian Dietzen (Palmer) has said that Breena died from Covid-19.
This is the first episode in the franchise to address COVID-19 and have the characters wear face masks.
This is the first time in 18 seasons that Gibbs says to a suspect, "you have the right to remain silent, anything you say can and will be used in a court of law".