This was part one of a two part episode
arc. Part two was called, "By Inferno's Light
." Garak intercepts a coded signal and becomes convinced that it's from his father
-- Enabran Tain, whom Garak believes was killed two years ago during a fail
ed invasion of the Dominion home world
. Garak wants to follow the signal to its source and look for his father but Sisko doesn't trust
him sends Worf along with him. Worf trusts Garak even less than Sisko does as is evident from the following exchange
Worf: At the first sign of betrayal, I will kill him. But I promise to bring the body back intact.
Sisko: I assume that's a joke.
Worf: We'll see.
Anyway, Worf and Garak follow the signal and it leads them to a huge Dominion invasion fleet which captures them.