I thought I was imagining things, but as she got closer I saw that my eyes were not deceiving me. The fashionable-looking student was sporting tight jeans ripped at the knees. In the days that followed, every second female I passed on the street seemed to be sporting similar, artfully slashed denim. Even a couple of young blokes were at it.
Was it 2015, I wondered, or was I having some strange hallucination of 20 years ago?
The ripped jeans thing died out around the time people started getting in a lather about the Millennium Bug. We're talking 1997, or in less enlightened parts of the country, 1998. It was a 1990s affectation.
One of the first things I did on landing in Dublin post-Leaving Cert in 1993 was to take a pair of scissors to my deeply uncool Lees. Not a good look then, or now. I wore them to college with a mix of pride and mortification.
But that was the 1990s and subsequent generations have more sense than to buy ripped jeans or, worse, do a little tailoring themselves with a sharp instrument, surely.
So why on earth has one of the most foolish sartorial fads in recent history come back to haunt us?
It seems that when it comes to fashion, music, television, you-name-it, the 1990s have returned with a vengeance.
And it shouldn't come as much of a surprise because people were obsessed about the 1980s in the 'noughties' and the 70s were a thing in the 90s (I still have scary flashbacks to the 'on-trend' bell bottom jeans and tie-dyed T-shirts an ex wore back then).
There is a 20-year cycle in the nostalgia business, it seems, with artists, musicians, fashion designers and other cultural movers and shakers often drawn back to their teens and early 20s when they hit their 40s.
Anyone seeking a good dose of 90s nostalgia in Dublin wouldn't have had to look far at the weekend. On Friday, Black Grape - the band Shaun Ryder formed after the Happy Mondays - were in town to play their 1995 album, It's Great When You're Straight, Yeah! in its entirety - and the following night, just up the road, a bunch of Irish 1990s DJs, led by Johnny Moy, played a late night show to commemorate the 20th anniversary of a celebrated concert at the Point Depot.
I interviewed Ryder some weeks ago and he rhapsodised about the 1990s, as well he might because it was such a great decade for him.
"It was a melting pot decade, man," he told me. "People weren't so set in their ways, in their little tribes: you could love grunge and dance and Britpop, a bit of everything, and that was okay. I think it's only now that we're beginning to see just how great that decade was when it came to music, and culture generally."
I neglected to tell him that I spent the early years of the 1990s sporting the centre-parted, undercut haircut he popularised, and a style worn by many young men until another Mancunian, Liam Gallagher, provided tonsorial inspiration.
Ryder, meanwhile, will be hoping that the 90s nostalgia continues until at least December when he takes the Happy Mondays' seminal album, 1990's Pills 'n' Thrills and Bellyaches, on the road, calling at Vicar Street, Dublin.
2015 has seen some of the 90s' most-celebrated bands return after a lengthy hiatus, with Blur, in particular, demonstrating a remarkable ability to turn back the clock. Their latest album, The Magic Whip - their first featuring all four original members since 1997 - is likely to be in those best-of polls come year-end.
You can hear 1990s influences everywhere. Another of the year's best albums to date, In Colour from Jamie xx, is heavily inspired by the decade's dance and trip-hop genres. Not that he has especially lucid memories of the decade, one would have thought: he was still in primary school when the 1990s came to an end.
Even the names chosen by young bands betray a fetish for the decade. The Scottish trio, 1990s, couldn't be more obvious, while rising Dublin outfit, Columbia Mills, take their name from a mid-90s Dublin venue on the Liffey that did a great trade during the city's clubland boom.
This may be hailed as a golden age of television, but 1990s TV shows are returning. The X-Files reboot will see David Duchovny and Gillian Anderson reprise their breakthrough roles while mercurial director David Lynch has been persuaded to deliver a new series of Twin Peaks. Both will air in 2016.
Twin Peaks was one of the key cultural touchstones of the 1990s, even if it did lose its way quite badly towards the end. Much like The Killing years later, it featured a storyline that unfurled slowly and over multiple episodes. There had been nothing like it on TV before and - in truth - nothing like it since.
1990s television of a less cerebral nature has been in the news of late thanks to the return of Chris Evans. The poster boy of 90s laddish broadcasting will replace Jeremy Clarkson on Top Gear and there was considerable excitement on social media a fortnight ago when he presented a one-off TFI Friday, his ground-breaking chat show which debuted in 1996.
Channel 4 cashed in on nostalgia for the decade the night after TFI Friday with an entertaining and occasionally illuminating look-back documentary, The Decade that Changed the World. Hyperbolic as that title might suggest, it's worth remembering that the 1990s began when few could conceive of the idea of the internet and the decade ended when most of us were wondering just how we had managed before it.
In truth, 90s nostalgia has been with us for a few years now but it feels as though it's reached its peak this year. Some would say it's even entering the realm of the absurd. Take designer Henry Holland, for example. He was all of 17 in 1999, and his debut menswear collection borrows heavily from that decade. His creations are, he says, inspired by the sort of clobber boys in north of England council estates wore that decade.
While many 1990s trends have been revived, others have been neglected. I thought there would be a nu-grunge movement 20 years on, but that didn't come to pass (in music, at least), although the lumberjack shirt has proved to be oddly enduring for both genders.
Similarly, the trend for very baggy and, for women, conservative clothing hasn't been resuscitated. My wife spent her college years dressed like a member of 4 Non Blondes, all big blouses and long skirts - a look that seemed to be de rigueur in Trinity in the early 1990s.
Today's spray-tanned, high-heeled and micro-skirted students wouldn't want to be seen dead in the gear, although the bouncy is a throwback, wwhether they know it or not, to 'The Rachel', the style popularised by Jennifer Aniston in Friends.
And, speaking of Friends, this milestone of 1990s US TV continues to hoover up new generations of fans some 21 years after the first series aired.
It's quite a challenge to scroll through the schedule on your smart TV and not find at least one channel showing the antics of Ross, Phoebe, et al.
It offers a reminder that the 1990s still seem so 'near', and yet so far ago in the distance.