Recruitment, Foreshadowing, and Future

That was indeed the case.

From the moment Frank met his contact, the other party had no intention of scrutinizing him.

After confirming that the secret signal and name were correct, the contact took Frank to a private airport and put him on a private plane.

Frank was the only passenger on the plane. After greeting him at the door, the only flight attendant just said to call for her if he needed anything, before she stayed away where Frank couldn't see her.

When he disembarked, she said, "Goodbye, sir," and the flight was over.

Frank sent a text using a prepaid phone which the contact gave him.

After he received a reply, he deleted the message, dismantled the phone, and tossed it into a dumpster outside the airport. He then took a cab to New York, after being away for months.

When he arrived at a park in Queens, he sat down on a bench and stared blankly at the dilapidated merry-go-round.