The first part is a relatively standard New Mutants story at this point: they skip school to go on a mission. Specifically they are going to investigate Bird-Boy's origin story. We find he was created as an experiment by the maddest scientist of recent years: the Ani-Mator. The Ani-Mator has been hired by Cameron Hodge and the Right to investigate a mutant cure but instead has done a double cross, and is splicing together human and animal parts to create a new race of Ani-Mates (not to be confused with the Ani-Men). He'd quite like to study the New Mutants, as well.
The battle soon becomes a three-way when Hodge and The Right turn up, angry at having been deceived by the Ani-Mator. There is general confusion, but the New Mutants eventually win. But there's a price. Douglas.
Douglas's death is curious. I knew he was going to end up dead at some point, but I thought the transmode virus was going to be involved. It seemed like such a natural thing to do. Instead, Warlock's absence (he and Bobby arrived late, from being in Fallen Angels) was the problem. Yay cliche avoidance?
The reactions to this, and to telly coverage of the other Fall of the Mutants stories, are the focus of #61. There is plenty of self-blaming, as you might expect. And having let one set of friends die, surely they should go to Dallas and help Illyana's brother (she tries but can't get there due to a gridlock in the omniverse). They decide to defy Magneto, one last time. And not without reason: the scenario of these kids being in a school has really fallen apart since their jaunt to the future and to space. They can't be confined so easily.