I saw this in the air as I was parking my car, and said, "Ooh." The silhouette from below at might at first be mistaken for a P-38 Lightning, but there's no central fuselage.

No, you are not seeing double.

This is the XP-82 Twin Mustang, developed late in the Second World War as a fighter escort for B-29s and used into the Korean War. In Korea, it was a useful stopgap until jet fighters like the Sabre could be put into service. It was also used as a replacement for the P-61 Black Widow reconnaissance plane.

Yes, it had two pilots. You figure that one of them must have felt pretty useless in a battle.