Add this fan's story to the list of reasons to love Keanu Reeves.
Alex Katsanos, the 14-year-old boy who struck up a conversation with the John Wick star at an airport, revealed to ET how he prepared for the moment during their flight from London to New York.
"When the plane was first boarding, I was pretty sure I saw him, but he entered the plane so quickly, so I wasn't sure," Katsanos told ET. "The whole flight from London I was thinking about, 'What if it is him? What should I say? What should I get him to sign?'"
Should the chance to approach Reeves arise, the teen tore a piece off a paper bag. "I brought a pen that a flight attendant gave me and kept those two things in my pocket for the duration of the plane ride," he said. Kotsanos also did his research, looking up the star online to see if there was any news about him being in London. "I saw that he was spotted at the Grand Prix," he noted. "That made me more confident that [it] was Keanu Reeves on my flight."
It also explains why Katsanos ultimately asked Reeves about the event, as Andrew Kimmel -- who shared a photo and description of the boy's encounter with Reeves on Twitter -- mentioned in a tweet.
"I was also asking general questions about why he was in London and what he is doing in New York and then he asked me questions like why I was in London and what stuff I did there," Katsanos recalled. "I was genuinely interested in what he had done in London and what he was doing in New York. I went to London because I recently graduated middle school and this was my graduation gift and when I was in London, I saw a couple musicals and shows there and this gave me more things to speak to Keanu about as we discussed the shows I saw, and it ends up he was in New York to see a Broadway show. It was great when he started asking me questions as well."
While the youngster admitted he was nervous when he first approached the star -- "I wasn't positive it was him" -- Katsanos described meeting Reeves as a "once-in-a-lifetime thing."
"It was really a natural conversation. He was very nice and we had a great conversation for around 10 minutes while we were waiting for our luggage. I still can't believe I not only got the chance to see him but to have a conversation with him and get his autograph," he described. "This is a once-in-a-lifetime thing and it was incredible."
As for that signed piece of paper bag, Katsanos, a self-professed fan of The Matrix, has plans to frame it and keep it in a special place in his room.
"When I first approached him, I was just planning on getting a picture and an autograph if I was lucky," Katsanos told ET, "but I am so glad that I ended up having this interaction with him."
He added, "I am still stunned that I had the chance to meet such a famous celebrity and get to have a normal conversation with someone as famous as that. I am really shocked this went so viral and I am so amazed that so many people are fascinated by the interaction I had with Keanu Reeves."