3 out of 5

Taking place in the Senso timeline, which is kind of fun in and of itself – that was a non-canon “conclusion” to Usagi, and here, Stan jumps to a bit before it to keep playing around in that world – Wherewhen is a pretty weightless tale, not making much use of the Turtles and kind of flippantly dealing with its cast in general. This is a problematic tonal mismatch: we have a pretty goofy time travel story (an evil robot menace named Dr. Wherewhen…), and then Sakai will dip into tragedy to align it with Senso for a panel, and run back to fighting rabbits and robo-dinosaurs. Admittedly Senso certainly fussed with B-movie / sci-fi / manga tropes, but it achieve that mish-mash with more of an epic sense; Wherewhen kind of shrugs these elements into place, its unepicness confirmed in a final sequence that has a time travel reveal hinted at in the first issue turn out to be… pretty pointless.

At the same time, it’s somewhat easy to let the imbalance was over you, because this is one of the most exciting multi-issue arcs Sakai has scripted in quite a while. It kind of makes sense that story came second: he needed a reason to pair the Turtles with Usagi (they chase Wherewhen into the timestream; they pop up in Usagi’s world, as the rabbit and his crew are on the march to battle Hikiji in the Senso timeline), and from then on, it’s just tossing major battles with page-filling armies at our heroes, issue after issue. The TMNT admittedly all blend into one character (Mikey seems to have a sudden grasp on science?), but Stan knows his own cast extremely well, and has fun poking at their alt-futures without having to worry about continuity, meaning he can weave in little moments with everyone amongst all the scuffles, and it’s just a page-turning blast of excellently arted action and satisfying asides. With apologies to Tom Luth, Hi-Fi Design’s colors are the most amazing additions to have happened to Sakai’s art, supporting and boosting his work positively across the board, and Stan’s work has hit another peak, masterfully juggling incredibly dense pages with action and character beats.

So, yeah, this is just a reason to pair giant robot samurai against Usagi, and maybe Stan wanted to use an IDW swan song (he’s moving back to Dark Horse) to interact with the Turtles one last time, and the resulting story is about as deep as that motivation. It’s definitely not nearly as jaw-dropping as Senso, and feels kind of tellingly pointless, even from the start. But: as each issue’s action heats up, you kind of don’t care.