By John Connor Coulston – November 10, 2018 03:25 pm EST Share 0 Comments 0 House of Cards killed off one of its lead characters during the final moments of the series finale.Spoilers ahead for House of Cards season 6, episode 8 (“Chapter 73”).The final season of the Netflix drama featured several key deaths, notably the off-screen death of Frank Underwood (Kevin Spacey). However, the most surprising death of all came during the final minutes of the series.Douglas Stamper (Michael Kelly), Frank’s right-hand-man, was killed by none other than Frank’s widow, President Claire Underwood (Robin Wright).Doug’s death ties back into the main mystery of the season: Who killed Frank? The public is told Frank spent his final night alive in the White House with his wife and died in his sleep in bed beside her.But Claire tells the viewer that is not the truth. Frank was not there when she went to sleep and instead, she found him dead in the other bedroom in the president’s suite. She thinks that he was murdered by an outside party, possibly someone hired by the Shepherds (Greg Kinnear and Diane Lane).However, it was Doug all along.Doug has a head-to-head confrontation with Claire at…