"It's Only a Paper Moon" is the 160th episode of the television series Star Trek: Deep Space Nine and the tenth episode of the seventh season. Directed by Anson Williams, the episode was written by Ronald D. Moore and based on a pitch by David Mack and John J. Ordover, who had previously written "Starship Down".

The episode serves as a sequel to "The Siege of AR-558", with Nog suffering from posttraumatic stress disorder and phantom pain following the loss of his leg.

After having his leg replaced after a battle injury (in "The Siege of AR-558"), and following months of rehabilitation at Starbase 235, Nog returns to Deep Space 9. He suffers flashbacks of his injury and feels pain in his new leg, even though the doctors do not detect any physical pain stimuli. The crew greets him warmly and intends to throw him a party, but Nog instead secludes himself in his quarters, sleeping most of the day and listening to a recording by Vic Fontaine of "I'll Be Seeing You" on repeat. When Jake becomes fed up with the constant repetition, Nog seeks out Vic in Quark's holosuite. After hearing Vic perform the song in every arrangement he knows, Nog convinces Vic to allow him to stay in his suite at the hotel for the night. Nog then decides to stay long-term, and with some disagreement among the senior staff, as well as Nog's family, and with assurances from Vic of his ability to help, counselor Ezri Dax consents to the idea to see where it leads.

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