Aaron Williams handed Simon Weaver’s high-flyers a half-time advantage with his third goal in as many games, but an Inih Effiong brace put the visitors in charge before Langmead’s late, late intervention.
From a Town perspective, the opening 45 minutes were fairly flat both on the pitch and in the stands. It was their visitors who played with the greater urgency, yet the first half went with the form-book as Williams smashed home Callum Howe’s header across goal from a 26th-minute Joe Leesley free-kick.
Barely a minute of the second period had elapsed when Anthony Jeffrey did Warren Burrell for pace down the Dover left and crossed for Effiong, who span and poked the ball past James Belshaw. The same player came within a whisker of grabbing a second moments later, while Jamie Allen hit the Harrogate bar.
Effiong held off a number of would-be tacklers and managed to force in a strike at Belshaw’s near post to give Dover the lead.
At the other end, Langmead twice went close with headers for Town, while George Thomson and Liam Kitching were to spurn chances to bring the hosts level.
And with four minutes of the additional six played, it seemed as though Dover’s time-wasting tactics had paid off until Langmead guided a header past Mitch Walker to level things up in dramatic fashion.
Harrogate Town: Belshaw, Howe, Langmead, Kitching, Burrell, Falkingham, Emmett, Thomson, Leesley, Muldoon (Beck 61), Williams (Thewlis 67). Unused substitutes: Cracknell, Agnew, Kerry.
Dover: Walker, Passley, Lokko, Brundle, Essam, Debayo (Okosieme 80), Jeffrey, Gomis (Nortey 71), Lewis, Effiong (Massanka 84), Allen. Unused substitutes: Sho-Silva, Adebowale.
Referee: A Miller (West Yorkshire).