Dollhouse S01E11

Haunted

 A wealthy woman named Margaret has been uploading her personality to the Dollhouse every month in the event that she is murdered. When she actually is murdered, DeWitt, who has since befriended her, imprints her onto Echo as part of her will; Margaret, posing as a pen-pal named Julia, decides to solve the case during her second chance. Margaret's prized horses turn out to be the key; with a little help from Boyd, who imprints Victor as a racehorse-owner, she solves the case and helps her family achieve some closure. Meanwhile, Topher signs Sierra out for an intensive "benchmark" imprint, which turns out to be that of a fellow gamer, nerd and friend, with whom he celebrates his birthday. Finally, Ballard brings November's prints into the FBI; when he asks fellow agent Loomis (Aisha Hinds) to run a scan, her computer spews out a multitude of names and then goes blank.