End of the Line is a story by Malcolm Shaw and John Richardson which ran in Misty from 12th August to 18th November 1978. It concerns a young girl named Ann Summerton who becomes convinced that her father, supposedly killed in an accident whildedigging a new Underground line, is still alive, and who discovers a subterranean village ruled by an apparently ageless Victorian aristocrat and mad scientist who is kidnapping people from the surface to use them as slaves. To add to Ann's troubles, her mother — who is about to marry a scheming chancer named Neville Chandler, who only wants her for her late husband's life insurance — refuses to believe her!
The story, which is frequently quite horrific (and extremely un-PC, the Victorian villain's forcibly physically altered slaves being referred to as "monsters" by the police) was eventually reprinted in 2017 in Misty (Collected Edition).
This story has no connection to the story End of the Line which ran in Doctor Who Monthly #54-55 in 1981.