What Happens to Gibbs' Boat on the Season 18 Finale of 'NCIS'? (SPOILERS)

The following contains spoilers from the NCIS Season 18 finale that aired on May 25.

Mark Harmon's NCIS character Leroy Jethro Gibbs is a pretty quirky guy, and so is the rest of the crew. However, fans everywhere would agree that the man with rules like, "Never go anywhere without a knife" and "Don't ever accept an apology from someone that just sucker-punched you" is the most interesting character of them all.

He can't stand modern electronics, likes to hold impromptu meetings in the elevator, and enjoys building boats to relax in his downtime. Gibbs has been building his boats by assembling each wooden craft by hand, never using a power tool. The crazy thing is that he doesn't sail them, and it appears that he just enjoys making them. His boat-building habit has been part of his character since the first episode of the crime drama.

He made one boat, Diane, after his wife, Diane Sterling (Melinda McGraw), and burned it after the marriage fell apart. Gibbs gave one away to his mentor, Michael Franks (Muse Watson), which was named after his deceased daughter Kelly (Mary Mouser). This season, fans finally got to see Gibbs out on the water in a completed vessel. Unfortunately, the boat ride goes awry, and fans were in for a rather shocking surprise in the season finale. Keep reading to find out what happened to Gibbs' boat.

As the end of Season 18 is wrapping up, viewers see Gibbs call Bishop (Emily Wickersham), who is driving somewhere, and tells her to check on Torres. When he's speaking with her, he is seen driving his new boat, Rule 91, to a lake. Before Gibbs hangs up, Bishop asks him what rule 91 means, and he tells her, "You're living it. When you decide to walk away, don't look back."

As the episode concludes, Gibbs is out on his newly christened boat. But the trip out to the lake with Rule 91 is not a pleasure cruise because he's looking for the body of the missing person that he and Marcie (Pam Dawber) had tracked down earlier in the finale. Then the unexpected happens, and Gibbs' boat explodes. Thankfully seconds later, fans are assured that Gibbs is alive because he's seen swimming off.

Unfortunately, viewers will have to wait to find out whether someone purposely planted the bomb to cause the explosion of Rule 91 or if Gibbs planted it himself so that the people that are following him will think that he's dead.

For some time now, a continuing question amongst NCIS fans has been, "How does Gibbs get his boats out of his basement?" On the show, it seems to be a running joke. When one of his agents asked on the series, "How do you get the boat out?" Gibbs told him, "Break the bottle."

Then another time, when Gibbs was asked, "How do you get the boats out of your basement?" all he did was smile and say nothing.

In the Season 18 finale, fans took to social media after seeing Rule 91 out of the basement and on the water. One fan tweeted, "Are we ever going to find out how Gibbs gets the boat out of his basement!!"

Another tweeted, “No, no, no, NCIS, you did not have us watch Gibbs build that boat for seven years to not let us see how he got it out of the basement. Don’t do us dirty like that.”

Gibb's method he uses to get the boats out of his basement is never mentioned, and there have been many potential answers. Out of all the answers we've read, the most likely is that Gibbs may build the boats on NCIS in pieces and then later put all the parts together outside of his basement. Maybe we will never know, or perhaps in Season 19, viewers will finally learn how Gibbs gets his boats out.