The city is squiffy with it. The crowds are addicted, and as for the players . . . Well, the way they have performed to put The Magpies top of the First Division makes you think they gulp a gallon of Keegan mixture before kick-off and take another slug at half-time.
But Newcastle on match day, locked gates at St James' Park, glory days back to Gallowgate, is the effect. It's the recreation, but not the source. To find that you need to journey 10 miles south from Tyneside to where the River Wear snakes its way round Durham's ancient castled and cathedralled peninsula and then straightens out alongside the green playing fields of the University. You have reached the Keegan honours course.
The teaching staff were getting changed on Friday morning. Ten o'clock and six chunky, joshing football men are crammed into a small, square office opposite the shower room. Piles of freshly laundered kit spill over from the chairs and corner cupboard. Two white telephones huddle at the end of the plain, plastic table pushed against the wall. One of them is clamped to the ear of what has once again become the most famous face in English football.
It's the civility you notice. There he is, in the midst of all the locker room banter, fielding phone calls with the polite, obliging, feet-on- the-table lucidity which once drove a frustrated rival to dub him 'Julie Andrews'.
Yet this is still football. The atmosphere is a lot more rumbustious than anything the Von Trapp family ever dreamt of, and next to Keegan now is his old playing mate and present right-hand man and buffer, Terry McDermott. No one in their right mind ever suggested Terry went near a nunnery.
McDermott has a warm, manic, Scouser irreverence laid over the history of a magnificent career with Liverpool and finally with Keegan at Newcastle in that legendary 'first coming' which saw the old club finally climb back where they belong. Of all the moves that Kevin has made, it is arguable that his best was his first; his unplanned, instinctive guess that he needed his old pal beside him.
With McDermott around dullness is never an option. Racing tips, night-out stories, reports on rival teams, are all related with an appetite so wide-eyed that sometimes the pupils float free in the eye socket. He may, like Keegan, have been out of soccer for years but he's a lot more than a joker. McDermott switches his tone to the direct, unflinching loyalty which saw the pair through during last season's desperate death- dance with relegation. 'His influence,' he said, pointing to Keegan patiently flannelling away on the telephone, 'is everywhere. It's tremendous.'
Nowhere more so than on the clipped grass, distant hockey pitches and handful of spectators of the Durham University training ground to which the team moved this summer. While it may be true that Kevin Keegan never intended to take up football management, out here he is in his element. The mane of hair may be greyer these days, and the muscled torso a bit slacker, but here again is the little inspirational dynamo whose fearless self-belief lifted him from an unpromising Scunthorpe apprenticeship to the very top of the European game.
'This is the best deal I have done since I came here,' he said looking across to where the playing fields gave way to a bridge over the Wear. 'I think a lot of our start is because everything we have done for the players' benefit is different. There is a change here. It's not just a name, not just one signing, it has to go right through the club.'
It starts even with the warm-up. Other clubs may still just jog round the pitch a few times and swing their arms a little. Keegan's Newcastle have drafted in exercise physiotherapist Steve Black, coach to boxer Glenn McCrory among others. For 20 minutes he ups and slows the tempo to get every muscle ready. 'In two months' time,' Black says uncompromisingly, 'this will be the fittest team in the country.'
The many who scoffed at the prospect of the Keegan-McDermott partnership making a professional fist of management, and plenty who still suspect this opening unbeaten run is too good to last, should be wary of the amount of delegation as well as physical involvement which is already the Keegan style.
As well as Black there is Jo Durie's coach, Leslie Apple, who comes twice a week to give running advice. There is the former Sunderland hero, Jim Montgomery, who takes the goalkeepers' training. When they all sprawl out in the office afterwards with McDermott, the first-team coach Derek Fazackerley and the others, you realise what Keegan is doing. Deliberately or otherwise he is recreating the atmosphere of the legendary bootroom at Anfield.
For all the energetic good humour outside, there is plenty of frank talk among the jokes. No doubting that standards are being set and have to be met, although there is little of the old players' disparagement of the new.
'I just go out there for the crack,' Keegan says. 'Terry Mack plays, we have the banter and at least we can still compete at a fair level. But players do things out there that I wished I could do, probably never could do. I don't expect much of myself and I take some kicks. I take a look sometimes and see if the player coming at me is in the team or out of it. I have kicked managers I have worked for. I understand all that.'
The eight-a-side match went to Keegan's side, 8-7, and amid much groaning the Viking-locked Kevin 'Killer' Kilcline was awarded the yellow jersey for worst player on the losing side. 'Killer' is out of the team at the moment. The joke of Friday's award was a little thin. Keegan understands all that too.
' 'Killer' will be back,' said the man the players now call 'gaffer'. 'He is a leader. He was a key signing last year. He gave us leadership on the pitch. Now besides 'Killer' I have bought (Barry) Venison and (John) Beresford, who are leaders. Kevin Sheedy, a very quiet leader who sets a tremendous example, and Paul Bracewell who is injured and who I can't wait to have back. Suddenly you find all the others become leaders as well.
'We haven't changed anything massive in the way we play. There is no way you can and go so quickly from the bottom to the top. We have pushed Gavin Peacock forward and tried to play more in the opponents' half. But you can't make a system and say, 'play that way'. You have to suit the players you have got.'
There is a genius in the simplicity, in the candour of it all. 'The club is still pounds 6.5m in debt. I wouldn't want that problem, but I know one thing: if we get gates of 28,000, it helps. For too long people have talked of this being an unlucky place. They even added a second Magpie outside the ground to stop thinking 'one for sorrow'. We are saying out loud we will be in the Premier League, that nothing will be bigger than this club.'
As the points get stronger the voice drops softer. He is almost whispering now, a man in the unreal and you would think unhealthy position of being hailed as a Messiah for the second time in the same place.
'Look,' says Kevin Keegan, 'if I was told I could go and manage Newcastle and would be very successful but couldn't walk down the street and talk to ordinary people, I wouldn't even think of it. I am doing it for the buzz it gives me and everyone.'
Bottle it up. It's heady stuff.