This review contains spoilers for Arrow Season 7, episode 9, which is Part 2 of the DC TV “Elseworlds” crossover event.
After seasons of teasing and namedropping, the Arrowverse finally takes us to Gotham for Part 2 of the “Elseworlds” crossover, introducing Ruby Rose as Batwoman (aka Kate Kane), and revealing why Oliver and Barry haven’t crossed paths with Batman in all their years of crime-fighting.
While ostensibly designed as the Arrow portion of the crossover, this episode has to do a lot of heavy lifting in other areas – both in establishing Batwoman enough to sow the seeds for the heroine’s potential spinoff series, and sufficiently explaining The Monitor’s motives so that the final part of the crossover hopefully won’t feel like a complete infodump when all is revealed.
Source: IGN.com Arrow: "Elseworlds, Part 2" Review