Despite (or perhaps aided by) a pilot that leaked online over the summer, Supergirl debuted with strong numbers on CBS.
Supergirl premiered with 12.96 million viewers and a 3.1 in the coveted 18-49 demographic when the final ratings for Monday night came in. The 3.1 ties Supergirl with Blindspot for the fall’s highest rated series premiere, though Supergirl out-rated it in overall numbers (12.96 to 10.6 million viewers).
The premiere’s ratings also grew slightly in the second half of the episode, which is a promising sign. Moreover, Supergirl was the second-highest rated show of the night, behind only its lead-in, The Big Bang Theory (15.87 million, 4.2 share).
Related: Supergirl series premiere recap: Up, up and away
According to Variety, Supergirl (tied with Blindspot) also boasts the fourth highest premiere ratings among adults 18-49 for any series in 2015 behind August’s Fear the Walking Dead (4.9), January’s Empire (3.8) and February’s Better Call Saul (3.4).
What do all these numbers mean? Essentially, Supergirl had a tremendous premiere, and a lot of people in the demographic that networks are particularly interested in reaching were watching. That is exactly what gets shows renewed, as long as the numbers last through the season.
The real test will come next week when it no longer has The Big Bang Theory, the highest rated show of the night and one of the highest rated shows on television, as a lead-in.
Related: Top 5 girl power moments from the Supergirl series premiere
Additionally, the series will have to hold its audience’s attention. This isn’t an easy task; Agents of SHIELD is currently rating about a third of its premiere numbers on ABC, and Fox’s Gotham is rating about half its premiere numbers. The Flash on The CW, on the other hand, serves as an exception to the rule as it continues to retain much of its initial audience.
After the episode, we also got a trailer for what fans can expect in upcoming episodes:
Supergirl airs Mondays at 8:00 p.m. ET on CBS.