The thing about this preview issue for Batman: Eternal, however, is that I don't think it's new-reader-friendly especially when there's a reference to the plotline concerning Man-bats (from Detective Comics #19) which Harper herself was in close vicinity of when that outbreak spread out. The importance of that throwaway line will be lost to someone who just happened to pick up this issue. I think by this point you must at least have read the earlier Snyder's Batman issues (particularly issues 12 and 18 since Harper Row appeared in those, so you'll also get a better sense of her character). I don't want to expound on the plot for this since I'm also trying to figure out how everything about it fits in the current continuity. When I finished, I have more questions than answers to provide for this review so I think we're all better off reading this together so my reviews will be more comprehensible by the next installments ahead.
But as a prologue to the upcoming series, this issue has done its job. It introduced the slightly awkward yet exuberant pairing of Batman and Bluebird for the first time. Batman looks very uncomfortable and yet willing to adjust his tone and attitude alongside his novice of a 'sidekick' (does it still hurt us Damian fans to know that some new kid is fighting alongside Bats? I have my reservations but I like Harper enough to give her a chance to win me over, as she tries to earn Batman's respect and trust as well). This issue also tries to tie in the aftermath of whatever happened in Detective Comics line-up whose events I assume has some parts to play in Eternal but that's my personal speculation so don't count on this being factual.
I'm getting ready to start reading the next issues (which are nine by now) but right after I wrap up Zero Year readings this week.