The second episode of the CW's highly anticipated four-way superhero crossover is on "The Flash" Season 3 Episode 8 titled, "Invasion." The series of events has already started with "Supergirl," and the story arc is officially introduced in "The Flash, " and will continue on with the 100th episode of "Arrow" and ends with DC's "Legends of Tomorrow."
The episode starts in S.T.A.R. Labs, where Cisco, Caitlin Snow, Iris and Joe West are debating how they will deal with Wally West exponentially increasing powers, with Iris' overprotective stance of asking the rest of Team Flash to lie to Wally about his condition. They agree, much to Cisco chagrin. Meanwhile H.R. Wells id making his presentation on how to restore Central City's faith in S.T.A.R. Labs when a satellite warning sounded, alerting them to a possible meteorite hurling towards Central City.
Rushing to the scene, the Flash discovers that the meteorite is actual a ship, with an up close inspection revealing that it is an alien ship. In the morning, Layla and ARGUS tried to cover up the incident, but revealing the truth about the Dominators to the Flash and the rest of the S.T.A.R. Labs team. She also asked Barry and his team to sit this one out.
Refusing to not do anything, he immediately went Star City to ask for the Green Arrow's help. Although Oliver Queen, John Diggle and Thea Queen agreed to join his crusade, they are still short a few more men. Barry then remembers the Firestorms, whereas Oliver suggested that they get the rest of the "Legends."
Cisco and Felicity were able to contact the Wave Rider, and will be waiting for them in a hangar owned by S.T.A.R. Labs, while Barry and Cisco went to another Earth to bring in an alien of their own. With Supergirl brought to the fold, Oliver suggested that Barry be their leader since he is the one that brought all of them together. Their first agenda is to acclimate themselves to fighting aliens by going up against Supergirl.
In a report by Deadline, the crossover episode from The Flash resulted in the highest rating they've had since the return of the Reverse Flash almost two years ago which garnered 4.66 million. Last night, The Flash increased 7% among 18-49s and 3% in total audience.