In the summer of 2017, Paris Saint-Germain broke the bank for attackers Neymar and Kylian Mbappe for a combined total of £360million.
PSG were consistent title challengers - and winners - in the French title, domestic matters were irrelevant. The pair's task was simple - guide the club to Champions League glory.
For a while it looked like Champions League glory at the Parc des Princes would not happen with Neymar and Mbappe's help. Both have been involved in reported fall-outs with the club and have agitated for moves away from France.
But now they're one game away from achieving the task they were brought in to do.
With Sunday's clash against Bayern Munich acting as the biggest games in their careers so far, Sportsmail looks at the journey Mbappe and Neymar have endured since they arrived in the French capital.
Both players arrived in Paris for the same objective - to steer PSG to European glory - but Neymar and Kylian Mbappe had different reasons for choosing the Ligue 1 giants as their next adventure.
The Brazilian attacker was already a key player at former club Barcelona, having helped the Catalans win the Champions League in 2015.
But in the same way that PSG wanted to be the main team in Europe, Neymar wanted to be the main man. The eccentric striker was always in the shadow of Barcelona legend Lionel Messi in Spain - the PSG move was his chance to show that he can shoulder the expectation that the Argentinian has.
On the other hand, Mbappe was already centre stage at Monaco. He had fired his former side to the Ligue 1 title at PSG's expense the previous season. But there was no way that the teenage sensation was going to reach his potential with a Monaco side whose star players were being cherry picked by all the major European clubs.
To become the player he is predicted to be, Mbappe had to do what Neymar always feared - be the understudy to the main attraction.
The young forward said in 2018: 'When I arrived in Paris, there was not a debate. It was him (Neymar) who was the superstar, that I had come to shoulder (and) help.'
But alongside Angel Di Maria, this lead actor-supporting actor role has created a frightening partnership which would make even Bayern Munich quake in their boots.
This season under German boss Thomas Tuchel has seen their partnership go to the next level. PSG have won 17 out of the 20 games Neymar and Mbappe have played together in 2019-20, losing just once.
Despite this clear success on the pitch, however, it has not been plain sailing for the duo, who have both been linked with moves away for the Parc des Princes.
Neymar especially did not do himself any favours during his first few seasons at PSG. The Brazilian has given off a misfit 'party image' whilst at the French champions which has not been met well by Tuchel.
While out injured with a metatarsal injury in 2019, Neymar held a wild 26th birthday party just days before PSG took on Manchester United in the second-leg of the Champions League.
The French side, with Neymar watching on the sidelines, threw away a two-goal first-leg lead to crash out of the competition on away goals. The headlines were not kind to the Brazilian attacker after that.
Last February, the same headlines appeared for the same reasons. Several of PSG's stars attended a wild party just days after losing to Borussia Dortmund in the Champions League.
In footage of the party, Neymar was jumping up and down on tables just days after returning from injury. His manager was forced to come out and condemn the actions of his players.
Last summer, speculation that Neymar was looking to return to Barcelona was intensifying. PSG's star attraction went AWOL for pre-season training and it looked like the relationship had gone beyond the point of salvation.
But Neymar has bounced back and even Barcelona have confirmed that a reunion with their former star is now impossible.
Like his Brazilian team-mate, Mbappe has been linked with a move away this year. A public row with Tuchel during a 5-0 thrashing of Montpellier in February raised speculation that all was not well between player and coach.
And with Liverpool and Real Madrid circling the situation regarding the French forward, there was even a suggestion that Mbappe may have outgrown PSG despite being just 20-years-old and playing for his hometown club.
Eventually, they cleared the air and now, all at PSG pushing in the same direction with the club on the brink of perennial glory on Sunday.
Their willingness to help each other out is clear to see. Since their arrival in 2017, Neymar has assisted Mbappe 15 times, with the favour being returned 16 times in the opposite direction.
Against Atalanta in the quarter-finals, the power of their bond shone through. The Brazilian was wasteful and looked lost until Mbappe came on with around half an hour to go.
Come full-time, Neymar had one assist and then laid on a crisp through-ball for Mbappe's assist for Eric Maxim Chupo-Moting's winner in stoppage time.
Both started against RB Leipzig in the last four and they took little time to start being a threat to their German opposition.
Only five minutes were on the clock when Neymar was running through on goal after an Mbappe killer pass. Seconds later, Mbappe had the ball in the net after Neymar's press allowed for an open goal, but the Brazilian was penalised for handball.
Neither have scored since the Champions League resumed this month - but neither have needed to. In the 63 games the pair have both played in for PSG, the French giants have scored a whopping 209 goals, averaging over three goals a match.
They need one more killer display to complete the job they were asked to do.