This article sets out to explain how the relatively unremarkable 2018 by-election result in which a sitting Labor candidate held her seat with a mediocre swing towards her resulted in the panicked removal of Prime Minister Malcolm Turnbull from office and his immediate resignation from the parliament. The combined Queensland state Coalition party, the Liberal National Party, convinced itself that it could win the marginal outer-metropolitan seat of Longman in Queensland but when its expectations were dashed, it became spooked and set in train a chain of events that ousted Turnbull and installed Scott Morrison as prime minister. Turnbull was widely seen by the Coalition party room as having run a lack-lustre campaign in the 2016 federal election, and not having performed well in the 2018 by-election campaigns. Perhaps unwisely, Turnbull made the Longman by-election a direct leadership contest between himself and opposition leader Bill Shorten. However, Labor’s tactics in the by-election ‘outmanned, outspent and out-campaigned’ the Coalition’s faltering campaign in the seat, causing the relatively unremarkable outcome in Longman to become a catalyst for a challenge to Turnbull’s leadership. When parliament reconvened, Peter Dutton became the ‘stalking horse’ who resulted in the rise of Scott Morrison to the top office.