James Cromwell plays Hanok in this episode. He has previously played 2 different characters in 2 TNG episodes. He played Prime Minister Nayrok in "The Hunted" (1990) & Jaglom Shrek in "Birthright: Parts 1 & 2" (1993). He is best known for his portrayal of the famous Zephram Cochrane (the inventor of warp drive) in the 2nd Next Gen movie "Star Trek: First Contact".
The trivia item below may give away important plot points.
This episode - a 'cat-and-mouse game' - is very similar to both the original Star Trek series episode "Balance of Terror," and the Star Trek film, _Star Trek: The Wrath of Kahn (1982)_, as well as the movie _Run Silent, Run Deep (1958)_. In this episode, it's the Defiant hiding in a gas giant as 2 Jem'Hadar battle cruisers pursue them. In "Balance of Terror," it was the Enterprise against a Romulan Bird of Prey, equipped with a cloaking device. In "The Wrath of Kahn", it was the Enterprise against an enemy-controlled Reliant, hiding in a nebula, and In "Run Silent, Run Deep" it was a US submarine against a Japanese destroyer. All 4 of these transmit tension as each party tries to outwit their counterpart in the other ship.