At the beginning supergirl was just heading home, flying through the night sky as she had just stopped a bunch of criminals from mugging a woman then, after this half way home she saw a suspicious hooded figure in a bank, but the thing that made him look most suspicious was that he was totally covered in black and that she felt a dark presence around him, so she flew down to check out this bad feeling, then suddenly a white van pulls up and then supergirl can hear shouting so then she races off quicker, so she see what's happening and suddenly, the man only clad in black is killing the robbers who were attempting to rob the store so she intervenes first she sends the robbers to the nearest jail.
Then she body smashes into the black figure as he is just about to kill one of the bank employees just about as she is going to make contact with the hooded figure, out of nowhere, she gets whipped with a pipe and then she gets smashed into the as the black suited individual now having decided to totally focus on her, disregards everyone else runs away from the scene.
20 minutes later
"Wow you are strong, I mean like... Wow, you have gotta puch but still not THAT strong like not as strong as Kal, but still pretty strong"
"WE will fight you later"
With that parting message the mysterious black figure disappeared.
Reeling from this she races home feeling slightly creeped out.