Using narrative criticism, this article weighs how the addition of Mark 16:9–20 continues, complements, and modifies the storyline of Mark 1:1–16:8. An example of changes to the Markan storyline is eschatology: whereas the Mark’s Gospel expects a short-term mission culminating in the appearance of the Son of Man within ‘this generation’, the Longer Ending points to an ongoing, open-ended mission, in which believers will perform miraculous ‘signs’ with assistance from the ascended Christ. Along with the authors of Matthew and Luke, then, the person who penned 16:9–20 merits recognition among Mark’s earliest interpreters and revisers.