Aside from being a heavyweight clash between two giants of Europe, Manchester United's Champions League tie with Paris Saint-Germain will feature plenty of sub-plots.
It represents the biggest test yet for interim manager Ole Gunnar Solskjaer, who has done an incredible job since replacing Jose Mourinho in December.
United have looked rejuvenated under the Norwegian and are currently unbeaten in 11 games - but opponents don't come much harder than PSG.
There-in lies another subplot, because even though PSG are one of Europe's finest, they will be without the injured Neymar and Edinson Cavani for the first leg on Tuesday night.
Their absences will most likely see Angel Di Maria start against United in his first appearance at Old Trafford since leaving for PSG in 2015.
Di Maria endured an awful year with United, so much so that he's regarded as one of their biggest ever flops in the Premier League.
And to be fair, he was that bad.
United recouped £44m of the £60m they spent to sign Di Maria from Real Madrid by selling him to PSG and since then neither party has looked back.
However, ahead of Tuesday night's game, the Independent's Miguel Delaney revealed some interesting details about Di Maria's infamous United exit.
After producing another poor performance, the Argentine winger reportedly received a public dressing down from Wayne Rooney in the dressing room. A huge argument erupted.
"Strong words were used" in the bust-up, while other United players described Di Maria as "talented but a complete fanny". It's no wonder he was sold in the end.
"It wouldn't be in Angel Di Maria's character to say so publicly, but the Paris Saint-Germain forward badly wants to prove a point to a few current Manchester United figures who personally questioned that character," wrote Delaney.
"Much of it stems from one explosive day in the dressing room when many of the players finally got fed up with the Argentine, and club officials decided it was time to sell up.
"After another disappointingly anonymous display, Wayne Rooney offered some robust criticism to Di Maria’s face. A proper argument erupted. Strong words were used.
"Stronger words are still used about Di Maria from some of his former teammates. 'Talented but a complete fanny' is a conspicuously consistent description. Others just felt he 'wasn’t giving 100%'."
Sounds like Di Maria didn't get along with a lot of his teammates at United - especially Rooney, who was United captain at the time and is never afraid to speak his mind.
Di Maria will be looking to exact revenge on his former club after the abuse he received.