The Decemberists are hard to describe.

You can leave the genre description at “folk rock,” and most people get the gist. There are indeed strummy acoustic songs with a hint of folky mandolins and swinging accordion melodies.

You could chalk up The Decemberists to the anything-goes nomenclature of “indie rock,” but that’s just too broad.

Some like to call the band baroque pop, and that’s closer.

But it’s the combination of all of the above — folky arrangements, blaring synthesizers, literary lyricism — that makes the Portland band what they are: a seven member band rendering rococo folk rock in beautiful, blushing musical color. They’re like a baroque version of the Beatles, more interested in turning clever phrases and literary tales of murder, queens, rogues and betrayal than in making radio hits.

But, you know, still incredibly catchy.

The Decemberists were all of that during Monday’s concert at the Holland Performing Arts Center.

For nearly two hours, the band delivered favorites such as “Oh Valencia,” as well as plenty of tracks from its new album “I’ll Be Your Girl.”

At first, the audience sat in the pristine theater and listened respectfully, which caused frontman Colin Meloy to make a few cracks about the relatively sterile feel of the show.

“I feel like I should talk very quietly in here. Very politely,” Meloy joked. “I appreciate an attentive audience. But we can occasionally talk to each other.”

About halfway through the show, Meloy continued his prodding before beginning the jaunty strumming of “Calamity Song,” a tune about the end of the world with lyrics that see Nebraska, in particular, go up in flames.

Fans rose to their feet, singing along with the tune and cheering at the mention of our state’s part in the apocalypse.

“I see how this works,” Meloy joked again. “We have to name-check your state to get you to stand up.”

After singing about “setting the lay of Nebraska alight,” Meloy shouted, “Sorry, Nebraska!” When the line about the state’s fiery fate was set to appear again, he changed it on the fly to Wisconsin, much to the delight of Husker fans in the audience.

Fans remained on their feet for the rest of the show, singing and clapping to their favorite songs.

That’s when things heated up. The Decemberists burned through its synthy new track “Severed,” which feels like something out of the “Stranger Things” soundtrack. The crowd immediately fell into the call-and-response of “We All Die Young,” which is something like a ’60s pop song having an existential crisis.

Fans sang to “12/17/12,” which Meloy played in tribute to the victims of the Route 91 Harvest Festival shooting in Las Vegas, on the anniversary of the tragedy.

And finally, fans sang to the excellently bright but dour new single “For Once In My Life.”

And then, as usual, The Decemberists closed with “The Mariner’s Revenge Song,” their 15-minute fan favorite about sailors, revenge, family and, uh, getting swallowed by a whale.

For this tour, the crew brought on an inflatable whale that hovered over the theater’s screaming audience as the beautiful, wonderful show came to an end.

“Thank you from the bottom of our hearts,” Meloy said. “See you around, Omaha.”