On Supergirl, universes collided when Barry Allen, AKA The Flash, finally found Kara, AKA Supergirl, after trying figure out that "weird space portal thing" a couple of times. Barry's first attempt to navigate between universes was in the first five minutes of the episode during a Thanksgiving dinner at Kara's place. There was a brief burst of light, but neither Barry nor his companion, Cisco emerged.
Nearly all of the highly-anticipated crossover episode would pass before Barry and Cisco made another attempt to move between universes during the final minute, and that left fans disappointed. Many fans took to Twitter to air their grievances.
Steve and Steven wrote, "CW definitely conned all of us Flash fans into thinking Barry and Cisco would show up as soon as the port opened." And, Jose Ramos tweeted, "So this was a crossover episode?? Only a minute of Barry and Cisco? Thanks for wasting my hype."
Or, maybe, Barry was in the entire episode? How could we possibly know? He is, after all, The Flash!