Luke Harris is the fiancé of Grimsborough forensics officer, Grace Delaney. He appeared as one of the suspects during the murder investigation of one of his Grimsborough students, Lisa Edwards, in At the End of the Rope (Case #35 of Grimsborough). Before that, he also appeared in the Additional Investigation of The Ghost of Grimsborough (Case #25 of Grimsborough). Lastly, Luke made a cameo appearance in The Rorschach Reaper (Case #41 of Grimsborough).