Every tv show should come with an option to explain who everyone is, what they previously did, and what happened in the past, in case you forgot. Because I always forget.
If some bloke walks into the scene and the main character suddenly looks unhappy, I want to be able to click a button and it says 'this is Bob, the main character's ex-husband, who had an affair in s01e03. As a direct result of this, the main character was in a car crash which led to the death of a harmless old lady and a secret crack addiction.'
@RolloTreadway Ooh, like the old Ceefax, but instead of pushing the red button, maybe the blue one instead!
@RolloTreadway Yes!!!
Web comics, too. (Some authors provide this in the comments, glory upon them.)
@RolloTreadway Audio description usually names everybody, if that helps. Some people find that the naming alone is enough to fill in the other gaps. @KaraLG84