The Flash shoots scenes for an episode (I believe 116, maybe 115) with Grant Gustin and a guest star.... and more.

THIS POST MAY CONTAIN NOTABLE SPOILERS FOR AN EPISODE OF “THE FLASH” EITHER 116 OR 115. If you do not want to read or view possible spoilers from the episode before seeing it, do not continue reading…

The Flash shoots a scene with Grant Gustin… plus an extra spoiler