Two tries in the opening two minutes of the second half set Bradford on the road to victory over Halifax in the first league derby between the sides since 2003.
The Bulls trailed 13-2 at the break after being forced onto the back foot for the majority of the opening half.
But Danny Williams and Jay Pitts crossed immediately after the break to turn the game completely on its head.
Full back Ryan Shaw converted both to put James Lowes’ side 14-13 ahead, with half back Lee Gaskell stretching their lead to 20-13 with a 50th-minute touchdown, converted by Shaw.
Adam Henry and Ben Heaton traded tries before Shaw sealed things for the Bulls.
It was Halifax who had taken the lead on nine minutes when the Bradford winger Chris Ulugia spilled a Scott Murrell kick and the Halifax skipper teed up Australian prop Mitch Cahalane for a barging touchdown under the posts.
Centre Steve Tyrer kicked the conversion for a 6-0 lead, although Ulugia was hauled down by Halifax full back James Saltonstall soon after as the Bulls made a rare line break.
The visitors doubled their advantage on the half hour when the winger Gareth Potts made a 70 metre break from inside his own 20.
Shaw got back to save the Bulls’ line, but held on too long and was dispatched to the sin bin.
That was all the invitation Halifax needed, Murrell again firing the final pass for the back rower Ross Divorty to score.
Tyrer converted, and when Murrell kicked a drop goal in the final minute of the half, the visitors led 13-0.
A penalty on the final play of the half from Shaw got Bradford on the scoreboard at 13-2.
But the real drama was still to come.
Bradford: Shaw; Williams, Purtell, Henry, Ulugia; Gaskell, Siejka; Clough, O’Brien, Sidlow, Olbison, Pitts, Addy. Subs: Ferguson, Baile, Lauaki, Fleming
Halifax: Saltonstall; Brown, Heaton, Tyrer, Potts; Johnston, Murrell; Cahalane, Kaye, Ambler, Divorty, Manning, Moore. Subs: Robinson, Spencer, Bracek, Maneely
Referee: Matthew Thomason