The team comes back from a mission or attack, there's some discussion about how it went. Over the course of the story, details about the past are revealed slowly.
It's clear that Keith is having some bad times from the conversation had after the Galra fight.
Keith looks at his Galra knife and continues having an existential crisis.
Keith leaves the castle ship for the first time, going off in the red lion into space.
It's after the second time Keith ejects into space, Shiro can't sleep because he's thinking too much, and almost goes out to pace the hallways, but meets Allura in the halls, and gives him a piece of space moon fruit to help stop him from not sleeping enough, after which Shiro finally goes to bed. -->.
stuff happens.
Shiro climbs into the black lion to attempt to figure out what to do to help Keith and the team. He unknowingly psychicly communes with the lion, who talks through him, and sagely gives him advice.
more stuff happens.
somewhere in the story, the pilots encounter a galra thing that is more easily fought as individual lions than as voltron. After seperating they can no longer form voltron again, it would take too much time sitting in one space, making them an easy target.
Keith brazenly speeds through a tight set of asteroids in his lion in a fit of anger, and the lion becomes concerned.
Keith disappears. The crew begins looking for him around the castle ship, until they realize his lion's gone. A pressing issue distracts the pilots from worrying about Keith.
Keith doesn't come back for longer than usual, complicating a plan to help a planet being scoured by the galra, and presenting a threat in the instance of a galra strike. The team starts getting a little bit panicked, Shiro leaves in the black lion to try and find Keith, something he'd never done before. He considers that this may have been something he should've done earlier.
we view some of keith's inner monologue without learning where he is. He's filled with (guilt?).
Shiro scans the area around the vastness of space but doesn't find Keith. He becomes exasperated, contemplating the vastness of the space around the castle ship, how Keith could be anywhere. But then he starts thinking about how Keith has been flying in the red lion, and sees that the asteroid field is a place where he could have learned to fly like that. He begins worrying that Keith and his lion got hurt, then heads over there.
Shiro scours the asteroid field for Keith, almost loses hope of finding him, then finally sees him in the distance, sitting on a very large rock.
Keith admits he thinks he might be a galra to Shiro, and worries the team would ostracize him if they found out. (there's more to this, i'm not finished.)