The grandfather of one of the victims made his fortune as the importer of Swiss Army Knives. In real life Michael Weatherly's father, Michael Manning Weatherly Sr., made millions as the importer of Swiss Army Knives.
The collection of lunch boxes found in a victim's home include ones featuring Quantum Leap (1989), Airwolf (1984), and Magnum, P.I. (1980), all of which were produced by Donald P. Bellisario (who also produces NCIS). Also, Scott Bakula of Quantum Leap is the lead character on NCIS: New Orleans (2014).
In a conversation about how one of the victims gained his fortune from his grandfather having been the first U.S. importer of Swiss Army Knives, Anthony goes on about how he loves Swiss things. He then says, "I even like Abba." Caitlin corrects him, noting that Abba is Swedish. He replies, "I don't think so."
It is possible that someone who worked on this episode was a fan of the 2000 Sci-fi Channel series, The Invisible Man (2000), as this is a near duplicate of a conversation from the pilot episode of the show.
Tony is thrilled about finding a Magnum, P.I. (1980) collectible lunchbox. The remake Magnum P.I. (2018) tangentially exists within the "NCIS" universe; it has crossed over several times with Hawaii Five-0 (2010), which itself has crossed over with NCIS's spin-off NCIS: Los Angeles (2009).
The final action takes place on Owl Creek Bridge, an homage to the classic Ambrose Bierce story Occurrence at Owl Creek Bridge (1961), immortalized by French filmmaker Robert Enrico in a 1962 short film that later ran on An Occurrence at Owl Creek Bridge (1964) TV series in the U.S.