The Flash Hits Season-High Ratings Thanks to Arrowverse Crossover

Barry Allen may be struggling with aliens and his own guilt, but "The Flash" is doing better than ever. Thanks to the "Invasion!" crossover between "Supergirl," "The Flash," "Arrow" and "DC's Legends of Tomorrow," the show -- which is midway through its third season -- has hit season-high ratings.

When the second installment of "Invasion!" arrived on "The Flash" last night, 4.09m viewers tuned in to see it, making it the show's most-watched episode since Season 1's "The Man in the Yellow Suit," which aired on December 9, 2014. "Invasion!" achieved a 1.2/5 rating in the adults 18-34 demographic and a 1.5/5 in adults 18-49, something the show hasn't done since last season.

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This year's crossover episode boosted "The Flash" with a +3% increase in total viewership from last year's crossover. The show also saw a +7% increase in adults 18-49, but matched its previous rating in adults 18-34. Overall, "The Flash" cinched the #2 spot in the 8-9pm hour for adults 18-34, tied for #3 with adults 18-49 and scored #1 for men 18-34 (1.4/7).

Notably, "The Flash" jumped a whopping +39% in total viewers between last week's episode and the crossover. Broken down, that's a +50% increase in adults 18-34, +36% in adults 18-49 and +75% in men 18-34. As a network, The CW reaped some major benefits as well; Tuesday was up +37% in total viewers (2.576m), +60% in adults 18-34 (0.8/3) and +29% in adults 18-49 (0.9/3). That makes last night's episode of "The Flash" The CW’s most watched Tuesday since February.

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Additionally, "The Flash" pulled in .5 million more viewers than "Supergirl's" crossover episode. However, it's worth noting that that particular episode also acted as "Supergirl's" mid-season finale and only featured a brief scene to tie it into "Invasion!". This scene was also repeated in last night's "Flash" episode.

Once in the “Arrow”-verse, Supergirl joins the Flash, Green Arrow, the Legends of Tomorrow and their friends in order to stop an alien invasion. With them, she faces down the Dominators, mind-controlling aliens who have grown so concerned about Earth’s metahuman threat that they have decided to stomp it out before it can reach the stars. "The Flash's" installment of the "Invasion!" crossover pit hero against hero after the Dominators mind-controlled Supergirl, White Canary, Heatwave, Spartan, the Atom, Firestorm and Speedy to turn on Flash and Green Arrow. Though Flash and Green Arrow were able to restore their friends to their original state, Team Arrow was abducted by the Dominators shortly thereafter, leaving Team Flash, the Legends and Supergirl behind to figure out how to rescue them.

Starring Grant Gustin as the Scarlet Speedster, "The Flash" airs Tuesdays at 8 pm ET/PT on The CW. The series also stars Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Candice Patton, Danielle Panabaker, Keiynan Lonsdale and more.

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