I don't remember if I talked about terror star trek au here so here it is
refitted science vessels erebus and terror are stuck in orbit of a planet they were attempting to surveil due to...insert any tos episode reason of why a ship would be stuck lol. tuunbaq inhabits this planet and ofc wants them to leave (here can take a form of some kind of mist and can go thru space)
transporters are not working (perhaps david young being the first victim of that...) and so shuttles are used to get on the planet (very dangerous as well due to storms)...gore and co try to explore but gore dies, and sir john is next
a skeleton crew is left on erebus (still unable to move) and terror is forced to make an emergency landing on the planet....the situation is bad. the food replicators are malfunctioning (on erebus too)
for the scurvy we went for some kind of crystal spores that affect people at different speed, showing up wherever they would bleed from
jfj is half romulan and ofc she keeps it secret, francis is a quarter klingon but everyone knows (perhaps having extra organs, mostly vestigial, that help him hold out more than others)
enterprise is sent to investigate the missing ships, with jcr in command as a commodore, which ofc has jim kirk miffed. they manage to get some people out just in time. bones having to make up a cure for the crystal thing. jfj and spock don't get along at first but perhaps a mind meld is needed at a point in sickbay....so they understand each other better...francis spends so much time in sickbay at everyone's bedside after...
misc stuff....yeoman jopson. goodsir a science officer who starts serving as ship's councilor. blanky navigator who started in science. collins does a space walk to fix erebus.
francis keeps wearing his science blue even as captain, jfj would be wearing gold but she insists on red and so she wears red.
the original messages about it are lost unfortunately so I don't remember all the details but having talked with @hesbianspock we managed to recall some things