I'm such a sucker for the trope where the caretakers get whumpee after they've been in captivity and discover there's some sort of implant in them. Maybe they were kidnapped and had a tracker put in them to trace them back to the good guys' base. Maybe theyre a living weapon and they've been chipped like a dog. Maybe its some highly unethical scientific experiment messing with their functioning, or a way of easily dispensing drugs to keep them under control.
Whatever the case, the new caretakers are bound to discover the implant at some point and will have to take it out somehow. Ideally with safe, planned surgery - but of course sometimes the circumstances are more immediate, more pressing. Nothing wrong with a bit of field medicine! And it'd be a real shame if the tech made it so they needed to be awake and unmedicated to remove it...
