SPOILER WARNING: The following article contains spoilers for X-Men Red Annual #1 by Tom Taylor, Pascal Alixe, Chris Sotomayor and Cory Petit, on sale now.
X-Men Red has been pivotal in detailing Jean Grey's adjustment to being alive once again following her return in the Phoenix Resurrection miniseries. Her main task as the new mutant messiah is to safeguard her species while achieving peace with mankind; a dream identical to that of her former mentor, Charles Xavier.
However, she meets resistance (as expected) in the form of another powerful psychic, Cassandra Nova -- who happens to be Professor Xavier's evil twin sister. Cassandra's intent is to commit mutant genocide and thus ruin her brother's legacy, with the added goal of making sure Jean feels responsible for the extinction of her people along the way.
As Cassandra gathers her arsenal, X-Men Red Annual #1 reveals she's lined up an extremely powerful rival to be Jean's enemy in the form of the X-Men leader's daughter from an alternate timeline, Rachel Grey.
Rachel, aka Prestige, has been established as a member of Kitty Pryde's X-Men Gold team over the past year or so, which makes her appearance here all the more surprising. However, it turns out she's been a sleeper agent all along, as revealed in a flashback to the aftermath of Jean's resurrection. The annual's entire story is a flashback, actually, showing Jean interacting with people close to her from her past life, one where she was married to Cyclops. Apart from old teammates, she reunites with Rachel (her daughter with Scott from the "Days of Future Past" storyline), whom she rightfully considers family.
Instead of a drawn-out conversation, the pair take to the skies, mentally connecting and establishing a bond of friendship and trust. This leads to Rachel accompanying her to meet Laura Kinney and Honey Badger as tribute to Wolverine, and to make amends with Black Bolt after the mutant-Inhuman war. The issue ends with Jean, now decked in her custom-made Red outfit, at Cyclops' grave, promising to make a better world.