time travel regulation organization where it’s not official policy, but it’s common practice for field agents to keep a binder at their desk with the names of their family and friends, their address, their anniversaries, their schedules, their passwords. everything you would need to steal an identity—virtually anyone who’s been a field agent for more than a year has had to steal their own identity at least once. the timeline they all work to protect is concerned with wars and presidents and major motion picture releases. some margin of error is allowed, and it’s not uncommon to find agents walking around dazed, coming back from a mission to find their best friend unexisted and a wedding ring on their hand that matches the ring of a stranger. some give up on all relationships, not even letting themselves love their siblings. some wear lockets on their missions, so that if the photo on their desk has shifted in its frame on their return, at least they have something left of the timeline that now never was. agent zhang, who works hebei-shandong-jiangsu AD 1850-2000, has eighteen different family portraits. in some some agent zhang has a wife, in some a husband, in some neither. three portraits have one child, one has four, one has seven, most have none. some are in courtyard houses. some are by white picket fences. many have parents, but the newest one has none. you ask agent zhang if it wouldn’t be easier just to let the alternate timelines go. agent zhang points at a child four portraits back, a little girl with a missing front tooth and a goldfish bowl clutched in her arms. “i never learned what that goldfish was called. i took her out for ice cream as soon as i knew she existed, and i didn’t even get to see her come home from school the next day.”