The episode focuses on whether one can ever truly "give up the ghost" of a dead relationship or if unresolved issues force people to keep running into their exes until they find closure.
Carrie attempts to extend an "olive branch" to Aidan, but their reunion is marked by coldness and awkwardness. Other Notable S4E5 "Ghost" Episodes [S4E5] Ghost Town
If you were looking for a different series, "Ghost Town" or "Ghost"-related themes often appear mid-season: Season 4, Episode 5: Ghost Town The episode focuses on whether one can ever