When Cobus Reinach rocked up at Franklin's Gardens, there was plenty of excitement.
It was predominantly sparked by YouTube videos, which showed the South African speedster turning on the turbos and leaving opponents in the dust.
But things didn't go all that smoothly in the first season for Saints' very own Road Runner, and some were left wondering whether his highlights reel had been deceptive.
After all, so many players come with big reputations and impressive clips, but never really string full, dominant performances together.
Reinach's bid to really show his worth was hampered by his compatriot, Nic Groom, with the pair sharing game time during the 2017/18 season.
In fact, the limited nature of Reinach's role is shown in his appearance count: he made 16 starts and 16 appearances as a replacement during his first campaign in black, green and gold, scoring seven tries.
Quite a few of the starts came when Groom decided to exit early, heading back to South Africa with immediate effect in April 2018.
That gave Reinach the chance, and the responsibility, he really craved.
Finally, he was the main man at Saints - and he was determined to make it count.
With Alex Mitchell promoted to a back-up position, Reinach took the Saints No.9 shirt with both hands.
Just 11 days after Groom's departure, Reinach was the star of the show as Saints secured their first win against Leicester Tigers at Welford Road for more than 11 years.
His speed and awareness proved too hot for the Tigers to handle on a sun-drenched derby day.
And it was to be a sign of things to come as, less than a year later, he was again instrumental in taking down the Tigers as Saints made it back-to-back league wins at the home of the old enemy.
That performance was far less unexpected as, by then, Reinach had established himself as a key cog in the Saints wheel.
He started 26 times last season, coming off the bench just four times, scoring a whopping 17 tries in all competitions.
He was joint top scorer in the Gallagher Premiership, alongside Sale Sharks wing Denny Solomona, and he secured Saints' players' and supporters' player of the year prizes.
The glimpses of class that had been seen during his first season at Franklin's Gardens became a far more regular occurrence.
Reinach pouched numerous intercept tries, continually blitzing opposition teams who were left wondering just how to stop him.
And he also improved other parts of his game, including his box kicking, which was an area that didn't quite work as he wanted during his first season at Saints.
He became the player that the club had dreamed of when they recruited him from the Sharks two years ago.
And now South Africa are feeling the benefit of Reinach's Saints journey, with the Bloemfontein-born star set to make his first World Cup appearance at the age of 29.
Having taken himself out of his comfort zone, Reinach has well and truly thrived.
And now his ticket to Japan is just reward for the determination he has shown not only to be Saints' starting scrum-half, but also South Africa's.
And who would bet against the son of a talented sprinter winning the race to be South Africa's main main at rugby's main tournament.
Whether he is or he isn't, you can certainly expect him to add a few more clips to that highlight reel in the weeks and months to come.