The last time these two teams met properly was in the similarly titled Civil War tie-in which also threw Marvel Boy into the mix. It was a hit-or-miss affair, offering a decent read for fans of the parent titles, but one that felt very inaccessible to newcomers thanks to a frankly massive cast of characters that you'd struggle to tell apart at first glance. Despite being slapped right in the middle of a crossover, it was largely ill-prepared to snag new readers and instead concentrated on feeding material to existing fans.
That problem has, unfortunately, not been addressed for this series. Let's hope you've all got your Young Avengers / Runaways Wikipedia entries open, because despite doing his best to service every character appearing here, Yost has to hit the ground running -- the issue picks up just before the appearance of the War-Skrulls as shown in the pages of "Secret Invasion", and there's very little time for reflection and introduction.
That aside, this miniseries feels like one of the better "Secret Invasion" tie-ins so far. It's always great to see the "Young Avengers" cast in action, especially alongside the "Runaways" kids. In both groups, Marvel has crafted iconic new characters that should have extensive lifespans in the Marvel Universe. Closely linking the two groups, while limiting their interaction with one another, only serves to feed the fanfare around the teams' infrequent meetings.
While the last Young Avengers/Runaways crossover relied on little more than the team's similar ages to link them, "Secret Invasion" actually presents far more in the way of an organic story possibilities -â€" with Earth under attack from the Skrulls, it's a happy coincidence that both of these teams already have Skrulls on their membership. Admittedly, in the case of Hulkling, he's only half-Skrull, but that's more than enough to garner the wrong kinds of attention, and is immediately seized upon by Yost.
Despite the quick pace of the book, Yost's character moments are in there and very fun to read, with Molly's dialogue a particular highlight. Meanwhile, the plot moves swiftly and purposefully, making it feel nice and lean, just as a miniseries should. Miyazawa's artwork is in particularly top form. If you're unsure how his manga-esque style (which fit the light relationship comedy of "Spider-Man Loves Mary Jane" so well) will translate to the large-scale action of this series, then don't worry about it -- the art is youthful and energetic, but doesn't fail to convey the scale and gravity of what's going on.
Certainly, "Secret Invasion: Runaways/Young Avengers" is a must-buy to fans of either parent series, but if you're looking for a place to get started on the property, don't be fooled by the idea of a crossover helping you pick things up. Do yourself a favor and go get those trades first so that you can enjoy this series properly.