Using the GREAT instrument aboard the airborne SOFIA observatory, we have imaged [C II] 157.74 micron and [O I] 63.18 micron line emission from a bright photodissociation region (PDR) associated with an ionized “bubble” located in the Nessie Nebula, a filamentary infrared dark cloud. A comparison of SOFIA data with ATCA radio data shows that the bubble has a classic PDR structure, with a uniform progression from ionized gas (traced by radio continuum), to photodissociated gas (traced by [C II] and [O I]), and on to molecular gas (traced by NH3) from the interior to the exterior of the bubble. The bubble is expanding into the Nessie Infrared Dark Cloud filament. At the location of the interaction, a luminous YSO has formed, indicating that feedback from the expanding bubble has triggered the formation of the YSO. Successive triggering of star-formation along the filament as the bubble expands may explain the large cluster of stars toward the western edge of the bubble and its unusual tear-drop shape.