– It was last call at MacLaren's, the Irish pub frequented by the characters on "How I Met Your Mother," but there was still time for an intoxicating treat. Eagle-eyed guests at a set party celebrating the sitcom's finale Monday spotted a high-end whiskey on the shelves and were delighted to receive as many free pours as they desired.

However, this is Hollywood, where you can't trust anybody, not even your bartender. Turns out the bottle was a prop, filled with a cheaper brand of booze.

The switcheroo serves as a metaphor for the show itself, one that seemed at times to be an elaborate Rube Goldberg machine with fanciful twists that led ever so slowly to answers on how Ted Mosby finally found his one true love.

But "Mother" has always been much simpler than that. At its heart, it's a fairly standard sitcom about five urban friends whose friendship has only gotten stronger and more endearing over the course of nine years.

"Around Season 4, people started to think the show was a big puzzle, like a game," said Neil Patrick Harris, who managed to ditch his teenage "Doogie Howser" persona for Barney Stinson, a bed-hopping executive who would slip on a suit just to check the mail. "They were trying to solve the show, and it was never intended to be something to solve."

That said, there are some tantalizing questions that need to be addressed in the one-hour finale, which looks at where the gang ends up 15 years in the future: Can Barney and Robin last? Will Marshall and Lily's teenage child need serious therapy? Is Ted telling this story to his kids as a — gasp! — widower? And can the cast and crew get to the finish line without crying their tear ducts dry?

"We're applying the word 'last' to a lot of weird things that don't deserve it," said the show's co-creator, Craig Thomas, a few weeks before taping the final episode. "Like, 'This is our last time we will order Chipotle for lunch,' and getting kind of misty-eyed about it."

Early on, it seemed unlikely that "Mother" would survive nine seasons. It never climbed into Nielsen's top 40 and got little attention on the awards circuit. But CBS boldly kept the series on Monday nights and it gradually built a cult audience in key demographics.

For the first four years, the cast — a mix of established performers and newcomers — held their breath while bonding fatalistically over their status as perennially "on the bubble."

That was actually a blessing, said Harris.

"Sometimes when a show is thrust into success right away, there's high expectations to come up with terrific stuff superfast," he said. "We got to develop this great vocabulary and weird little inside jokes so that by the time fans started watching us on Netflix and in syndication, we had found our own voice. I liked the slow-burn elements to our show."

While the cast and writers get a lot of credit for keeping the show fresh and inventive, attention must be paid to Pamela Fryman, who directed nearly all of the 200-plus episodes. Many involved traveling back and forth in time, dazzling musical numbers and delicate, highly choreographed sequences like the "two-minute sidewalk date" that was captured in one extraordinary, seamless shot.

"Every episode I read I'd go, 'How am I going to do that?' " Fryman said. "And somehow, with the help of the cast and all the people you don't see behind the scenes, we'd get it done. I would have been crazy to go anywhere else."

Jason Segel, who plays Marshall, credits Fryman for creating a pleasant work environment.

"This has been like the nicest place to come for nine years and nobody could get out of line without feeling really dumb for doing it," he said. "I've learned a lot just from being around Pam."

Fryman is hoping to extend her relationship with Thomas and writing partner Carter Bays. She's signed up to direct the pilot for "How I Met Your Dad," a spinoff starring indie film darling Greta Gerwig.

If the show gets picked up, Thomas and Bays say it's unlikely that any of the current cast members will pay a visit, at least not anytime soon.

But Harris thinks a reunion isn't out of the question.

"I don't know," he said. "Maybe at the comic-book conventions when we're all hard up for money."