Exeter remained on course for the Aviva Premiership title play-offs after claiming a dramatic injury-time victory at Kingsholm.
Substitute lock Aly Muldowney's last-gasp try, which was awarded on the judgement of television match official Tony Spreadbury, and converted by Muldowney's fellow replacement Gareth Steenson, gave the Chiefs a seventh win from their last eight away games in all competitions.
They looked to have blown it when Gloucester staged a stunning fightback from 18-6 adrift approaching the hour mark. However, The Chiefs unravelled in spectacular fashion as Gloucester scored three converted tries during a devastating seven-minute burst.
Wing James Simpson-Daniel, fly-half Freddie Burns – courtesy of a brilliant solo try when he caught his own kick ahead one-handed – and replacement scrum-half Nick Runciman all touched down, while goalkicker Burns finished with 17 points.
Exeter looked as though would head back down the M5 with only a losing bonus point, secured by Steenson's late penalty, and they would have been kicking themselves after prop Craig Mitchell and wing Matt Jess claimed first-half tries.
Fly-half Ignacio Mieres added two penalties and a conversion, but just when it looked as though Exeter were finished they dug deep to claim a first win in their history at Kingsholm.
It represented a memorable recovery act – and a considerable show of character – leaving Gloucester to reflect on playing their part in a 55-point thriller, but with nothing to show for it apart from a losing bonus.
Gloucester recalled some impressive back division firepower in Simpson-Daniel, Charlie Sharples and Eliota Fuimaono-Sapolu, while Exeter were unchanged after crushing Sale 37-12 last time out.
A television match official was in place at Kingsholm as part of a four-fixture experiment that could be rolled out across every Premiership game next season.
Only games televised live currently have a TMO, but Premiership clubs might expand that for all league fixtures next term at a cost of around £350,000, with Gloucester's clash against Exeter launching the trial period.
Former international referee Spreadbury was handed the task on a glorious afternoon made for attacking, open rugby, and it burst into life after 20 minutes.
The two packs went at it hammer and tongs early on, and after Burns had kicked Gloucester ahead, Exeter bounced back by launching a thrilling attack through flanker James Scaysbrook.
The ex-Bath forward delayed his pass perfectly, but scrum-half Haydn Thomas knocked on with the line beckoning and Gloucester stormed upfield through a Sharples-inspired break that was only snuffed out when Chiefs flanker Tom Johnson covered brilliantly.
Exeter, though, were not to be denied, and they went ahead after 23 minutes when Mitchell powered over between the posts following a delicious off-load by hooker Chris Whitehead, with Mieres' conversion making it 7-3.
The Chiefs then should have had a one-man advantage for the game's remainder, but Gloucester and Scotland lock Jim Hamilton enjoyed a major let-off.
Hamilton appeared to punch Thomas, who fell to the floor on the halfway line, yet referee Greg Garner opted for a yellow card after consulting with his assistant Don Helme.
Citing officials are sure to study the footage closely, and Hamilton might not have heard the last of it, but Exeter made him pay by collecting a second try just before half-time.
Crisp passing was again the Chiefs' trademark, with Jess crossing unmarked wide out. Although Mieres missed a difficult conversion attempt, Exeter were outstanding value for their lead.
And they almost extended it on the stroke of half-time when lock James Hanks looked to have touched down, only for Spreadbury to rule otherwise.
But dominant Exeter still had the final word through a Mieres penalty that made it 15-3 at the break.
Burns cut the deficit to nine points with a penalty two minutes after the restart as Hamilton reappeared, only for Mieres to cancel out that strike from short range after Gloucester put themselves under pressure by fumbling possession in defence.
The home side desperately needed to increase their tempo, having looked ponderous for too long, and they finally breached Exeter's defence after 58 minutes through a trademark overlap try poached by Simpson-Daniel and converted by Burns.
It meant Exeter were being asked serious questions for the first time in a contest they had otherwise dominated, and they did not have the answers as Burns and then Runciman glided through their defence.
Steenson's strike sparked hopes of a late Exeter recovery, and it was duly completed when Muldowney and Steenson combined to produce the final scoring act of a pulsating contest.