Rodgers and Hammerstein. Lerner and Loewe. Comden and Green. Theater fans know those great teams but "Ahrens and Flaherty" does not spring to mind so readily.

The only one of those teams still creating musicals, lyricist Lynn Ahrens and composer Stephen Flaherty may not have the name recognition but musical theater lovers know their varied, tuneful work. Their "Anastasia," an elaboration of the animated film about the possibly-long-lost heir to the Russian throne, opens Tuesday at the Orpheum Theatre. "Seussical," "Ragtime," "Once on This Island" and "Rocky" are just a few of their other accomplishments.

Actually, the team tackled "Anastasia" twice. The movie tries to shoehorn tragic Russian history — Bolsheviks executed the Romanov royal family in 1918 — into a traditional fairy tale, even turning adviser Grigori Rasputin into a stock villain. The stage version reportedly pays more attention to history, introducing a Communist hero who falls for the title character, an apparent survivor of her family's massacre. More than a dozen Ahrens/Flaherty songs that weren't in the movie help tell that new story.

Here are several reasons, on stage and off, why you should know about Ahrens and Flaherty.

'Schoolhouse Rock'

If you're a child of the 1970s, there's a good chance you still can recite/sing the entire preamble to the Constitution, and Ahrens is the reason. She got her start in the music business when she was a secretary who met David McCall, creator of the "Schoolhouse Rock" animated shorts that appeared on ABC, starting in 1973. They worked at the same ad agency and she apparently took her guitar to work. So he asked her to take a crack at writing catchy tunes that hid lessons about grammar. She started with "A Noun Is a Person, Place or Thing" and went on to write and sing some of the series' most iconic numbers, including "Interjections" and that preamble, which you probably already know begins, "We, the people, in order to form a more perfect union ... "

Honors

Although the 1997 "Anastasia" film didn't achieve the Disney-like success it aimed for, the composing duo earned a pair of Oscar nominations, for their score and for "Journey to the Past," the song that also closes the first act of the stage adaptation. They've won numerous other awards, including a 1998 Tony for the "Ragtime" score.

'Ragtime'

Speaking of the adaptation of E.L. Doctorow's classic novel, "Ragtime" lost most of the other 1998 Tony Awards to a little behemoth called "The Lion King." But its reputation has grown with a Broadway revival and numerous regional theater productions, including the acclaimed 2016 Theater Latté Da staging that traveled to Seattle the following year and Sarasota, Fla., the year after that. (Its director, Peter Rothstein, would be hand-picked to work again with the words of book writer Terrence McNally on the Texas premiere of his final play, "Immortal Longings.")

Ice cream bars

Back to the 1970s, do you remember "What would you do for a Klondike Bar?" or "Bounty, the quicker picker-upper?" Ahrens wrote those advertising earworms.

'Seussical'

Like "Ragtime," "Seussical" has shown that Ahrens/Flaherty collabs have greater appeal for audiences outside New York. The Broadway production ran just six months but remains a staple of community groups and high school theaters, which made it the country's most-produced show in the mid-2000s.

'Twenty Million People'

The musical adaptation of the Peter O'Toole comedy "My Favorite Year" doesn't get produced all that often but its first number, "Twenty Million People," appears on many experts' lists of the best openers in musical theater history. (It also showcased the talents of Andrea Martin, who was nominated for a Tony Award.)

'Dancing Still'

The team has been developing several new musicals. One, once called "Little Dancer" but now called "Marie, Dancing Still," is inspired by Edgar Degas' famed "Little Dancer Aged 14" statue and explores the bond between the French artist and the young ballerina who posed for him. Another musical, "Knoxville," is adapted from the James Agee novel, "A Death in the Family." Both have had regional productions that were billed as pre-Broadway runs but neither has hit the Great White Way yet.

'Anastasia'

Who: Lyrics and music by Lynn Ahrens and Stephen Flaherty. Book by Terrence McNally. Directed by Darko Tresnjak.

When: 7:30 p.m. Tue.-Thu., 8 p.m. Fri., 2 and 8 p.m. Sat., 1 and 6:30 p.m. Sun. Ends Dec. 19.

Where: Orpheum Theatre, 910 Hennepin Av. S., Mpls.

Tickets: $40-$146, 800-982-2787 or hennepintheatretrust.org.