Every potential pairing in Friday's draw is loaded with history, and titles. Defending champion Real Madrid, Barcelona, Bayern Munich and Juventus have combined to win the competition 21 times, with 16 runner-up finishes.
Still, two possible storylines stand out.
Bayern coach Pep Guardiola could face former team Barcelona for the first time since leaving in 2012 after a trophy-laden four-year spell that included two Champions League titles. And a Barcelona-Juventus pairing would reunite Luis Suarez and Giorgio Chiellini for the first time since the Uruguay forward bit the Italy defender during last year's World Cup.
Because of his actions, Suarez missed three Champions League matches while serving a four-month ban imposed by FIFA. But he is back now, and so is Juventus, which is returning to the semifinals after a 12-year absence.
"Considering the lineup, I'm not even curious to watch (the draw)," said Juventus goalkeeper Gianluigi Buffon, who played on the losing team in an all-Italian 2003 final against AC Milan.
That was the last time Juventus made the final, ending a 30-year run in which the team won two titles and reached the final seven times. Andrea Pirlo, now Buffon's teammate at Juventus, played on that Milan side which won a penalty shootout after a 0-0 draw.
On Wednesday, Juventus advanced in classic Italian style: Resolute defence in a 0-0 draw at Monaco after scoring the only goal in the first leg from a disputed penalty.
The other three semifinalists, who each have scored at least nine goals more than Juventus in the competition, have been regulars at this stage lately. And a Bayern-Madrid semifinal pairing would be a third time in four years.
Last year, Madrid humbled Guardiola's new team 5-0 on aggregate, including a surprising 4-0 win in the second leg in Munich. In 2012, it was Bayern which advanced on away turf, winning a penalty shootout in the Santiago Bernabeu Stadium after the teams traded 2-1 home wins.
In 2013, it was five-time champion Bayern which gave Spain a semifinal humiliation, beating Barcelona 7-0 on aggregate while Guardiola was on his one-year sabbatical.
Another "clasico" semifinal — meaning another Lionel Messi versus Cristiano Ronaldo drama with the all-time tournament scoring record at stake — would repeat a testy 2011 meeting. Then, Barcelona advanced 3-1 against a physical Madrid team coached by Jose Mourinho.
Madrid, now under the calmer Carlo Ancelotti, won a record-extending 10th European title last season. And the Italian can become the first coach to win four European Cup or Champions League titles in the competition's 59-year history with a repeat.
Ancelotti, who coached Juventus for two years early in his career, later led Milan to the title in 2003 and 2007.
Ancelotti also played on the Milan team which, in 1989 and 1990, was the last to win club soccer's most coveted trophy in back-to-back seasons. No team has successfully defended the trophy since the Champions League format began in 1992.
The first legs of the semifinals will be played on May 5-6, with the return matches on May 12-13. The final will be played on June 6 at the Olympic Stadium in Berlin.