As the big bad of the Marvel Cinematic Universe, Thanos is shrouded in mystery. With all of the Infinity Stones, he became the most powerful being in the galaxy and was able to wipe out half the universe.
But how was he able to figure out that the Guardians Of The Galaxy were heading to Knowhere in an attempt to intercept the Reality Stone?
In Avengers: Infinity War, the Guardians only learned about Thanos' quest to obtain the Infinity Stones after they ran into Thor. It was the God of Thunder's knowledge of the Stones and his deductions that lead two-thirds of the Guardians on the path to the Reality Stone.
When the Guardians arrive on Knowhere and attempt to take Thanos by surprise, they learn that the Mad Titan has already obtained the Reality Stone and manipulated the team into thinking they had the drop on him. After Gamora thinks she killed Thanos, he reveals the true reality that shows Knowhere is engulfed in flames, and that he has half of the Infinity Stones.
Thanos is shown to be lying in wait of the Guardians and has sprung a trap for them so that he could capture his daughter Gamora, who happens to know where the Soul Stone is. The movie makes it seem like this was his plan all along.
But there's still a major question left to be answered in how Thanos knew the Guardians, specifically Gamora, would be meeting him on Knowhere?
Did Thanos know that Thor would survive his use of the Power Stone to destroy their refugee ship? Did Thanos know that the Guardians would discover his body? Did Thanos know that Thor would tell the Guardians about Thanos? Did Thanos know Thor would tell them he knows the Reality Stone is on Knowhere? Did Thanos know that Gamora would then travel to Knowhere in an attempt to stop him?
Given that Thanos knows that Gamora knows where the Soul Stone is hidden, this seems plausible. But this is a major logic leap for the movie to make in order to move the story along.14comments
It's not so much a plot hole as much as it is a plot convenience, but it still begs the question: How did Thanos know the Guardians and Gamora would meet him on Knowhere? Did he sense the Guardians' ship arriving with the Space Stone, and quickly used the Reality Stone to achieve his ends? Did Gamora make Thanos' quest easier through sheer convenience?
These aren't questions that Avengers 4 will solve, but maybe if enough people bother the Russo Brothers about it, they'll provide an explanation.