At the end of it all, Fery stood on Centre Court with his hands on his hips, shaking his head in sheer disbelief as the crowd rose to their feet.
Swiss great Roger Federer, watching from the Royal Box, was among the thousands inside Wimbledon's centre stage living each point of a captivating conclusion.
Such theatre had appeared unlikely when Dimitrov, having turned the match in his favour following a superb opening set by Fery, twice took the lead in the fourth set.
But Fery - as he has done all week - refused to be put away and leapt into the air in celebration after forcing a decider.
Former world number three Dimitrov was aiming to reach the quarter-finals after his previous bid ended in tears on this exact stage 12 months ago, when he retired injured while leading eventual champion Jannik Sinne by two sets to love.
But Fery never flinched, even as the tension and expectation ramped, becoming just the sixth British player in the Open era to reach the Wimbledon men's singles quarter-finals.
Having never previously gone beyond the second round at a major, Fery will now face Italian ninth seed Flavio Cobolli for a place in the semi-finals on Wednesday.