It was the hosts that made a dream start when centre Adam Powell touched down on seven minutes.
But Blues showed plenty of heart and endeavour and were rewarded when wing Harry Davies scored on his debut after a sweeping attack.
Further tries, though, from scrum half Ruki Tipuna and hooker Rob Vickers – while Blues’ back row Rory Watts-Jones was yellow carded - saw Falcons seemingly take control with a 21-7 lead by the break.
However, the drama duly exploded into life in the second half as two tries in six scintillating minutes from Tom Davies and Watts-Jones shell-shocked the Falcons and turned the game on its head.
A penalty from Simon Humberstone then put the region ahead with 22 minutes left and in a tense finale two missed penalties from Newcastle proved vital as Blues claimed a huge cup scalp.
Newcastle made ten changes from the side that lost the LV=Cup opener with Northampton as the big guns all returned ahead of the Premiership resumption next weekend.
Blues also rang the changes with Amorosino the solo survivor from the team that started against Munster in the PRO12 as young stars and fringe players were given a chance to impress.
The Falcons came out flying and were straight on the attack with Blues forced to repel several waves of attack with the prominent Alesana Tuilagi bulldozing past men early on.
A first penalty allowed Newcastle to kick to the corner and, after the driving lineout was halted, play went in field and several strong runs opened up space for Powell to crash in.
Blues looked to respond with Watts Jones and skipper Jenkins carrying ball forward and taking the attack to Falcons before a counter attack was brilliantly finished by the visitors.
Tom Williams hacked ahead, after Blues had ripped ball away, and Fish and Socino tussled for the ball close to the line before it spat out to wing Davies to pounce for his try. Simon Humberstone added the extras to level the scores.
The game was swinging from end to end and it was Falcons who struck next on 16 minutes as scrum half Tipuna broke tackles and darted over from close range after a five-metre lineout.
Newcastle were starting to dominate territory with slick handling allowing Noah Cato and Gonzalo Tiesi to combine down the left, with Garyn Smith and Fish working hard to shut down space.
However, Blues also looked dangerous with ball in hand as Lucas Amorosino released Tom Williams with a neat inside pass and the wing glided past tackles to make 20 metres.
A yellow card to Watts-Jones, though, put Blues on the back foot and Falcons ruthlessly exposed the numerical advantage as Vickers was driven over from close range.
The Blues forwards looked to hit back with Rhys Williams and Jevon Groves offering themselves up around the fringes before Fish kicked in behind and Tom Williams looked to rattle Tait.
One last attack in the half saw Blues work the ball left and Jenkins break the line with sweet line, but his inside pass was too hot and the chance was gone.
Watts-Jones returned to the fray at the start of the second half and made a line break immediately before Fish and Dicomidis followed suit as Blues looked to mount a second half fight-back.
Falcons suddenly looked rattled for the first time and, when Tipuna was yellow carded for dangerous tackle, the driving lineout was finished by Davies to cut the lead to 21-14
Fish drilled Falcons back further with a sublime kick over the head of Tait as Blues looked to use extra man.
And seconds later try number three arrived as a charge down kick was pounced up on by Watts-Jones. Two tries in six dramatic minutes and the lead was two points.
Sustained pressure from Blues continued and a penalty gave Humberstone a kick to take the lead that he drilled over.
The penalties were now flowing against the Falcons who were struggling to get out of their own half with another driving lineout going close before the hosts snuffed out at attack wide right.
Tomos Williams was introduced on the left wing for Blues, replacing try scorer Davies, while Blues continued to adopt a clever territory game to force Falcons to attack from deep.
However, when a long kick ran dead it gave Newcastle a rare attacking platform to strike. Several scrums later and the penalty was awarded, but Socino dramatically missed the kick from in front.
Moments later Rory Clegg also missed as his kick pulled up short and right of the target as Blues breathed a sigh of relief.
The last two minutes saw Falcons mount several waves of attack, but when a spilled pass on the touchline was picked up by the officials the final whistle sounded to spark visiting celebrations.
07m Powell t Socino c 7-0
11m Davies t Humberstone c 7-7
16m Tipuna t Socino c 14-7
29m Vickers t Socino c 21-7
44m Davies t Humberstone c 21-14
50m Watts-Jones t 21-19
58m Humberstone p 21-22
Cardiff Blues: 15 Dan Fish, 14 Tom Williams, 13 Lucas Amorosino, 12 Garyn Smith, 11 Harry Davies (Tomos Williams 65), 10 Simon Humberstone, 9 Tavis Knoyle; 1Thomas Davies, 2Rhys Williams, 3 Scott Andrews, 4 Lou Reed (Normandale 69), 5 Chris Dicomidis, 6 Jevon Groves (Roach 69), 7 Ellis Jenkins (c), 8 Rory Watts-Jones
Replacements: 16 Ethan Lewis, 17 Callum Lewis, 18 Dillon Lewis, 19 Miles Normandale, 20 Ben Roach, 21 Tomos Williams, 22 Will Thomas, 23 Jack Phillips