Entertainment Theater review: 'If/Then' -- 3 stars Idina Menzel during a performance of "If/Then," at the Richard Rodgers Theatre. Photo Credit: Polk and Co. By MATT WINDMAN. amNewYork theater critic Updated March 30, 2014 6:39 PM Print Share fbShare Tweet Email As one of the few new musicals not based on a familiar film or pop song catalog (or anything else for that matter), "If/Then" certainly is a breath of fresh air. And despite nagging issues with its overall concept and divided story lines, it is a smart, romantic piece with a well-crafted soft rock score and great performances all around. It also functions as a dynamic and demanding star vehicle for Idina Menzel (aka Adele Dazeem), who is joined by many other strong musical theater performers including Anthony Rapp (Menzel's "Rent" co-star), LaChanze, James Snyder and Jenn Colella. Menzel plays a city planner in her late 30s who moves to New York to restart her life. In the style of the 1998 Gwyneth Paltrow flick "Sliding Doors," a seemingly mundane decision leads to two vastly different paths of life, one that is marriage-oriented and the other consumed by career advancement. The musical constantly switches back and forth between the parallel versions of her life. Even with color-coded lighting to help guide the audience, the convoluted structure can be confusing, clunky and disruptive. While "If/Then" never quite captures the intensity of "Next to Normal," also written by composer Tom Kitt and lyricist-book writer Brian Yorkey, it effectively explores the instability of contemporary urban life. Menzel, who is hardly ever offstage, shows off her powerhouse vocal abilities while also conveying vulnerability. As Menzel's friends, Rapp adds a scruffy, warm presence and LaChanze lights up scene after scene with verve. Stylishly directed by Michael Greif on a sleek set containing a massive tilting mirror, "If/Then" may not be a triumph but it is contemplative, heartfelt and fashionable in a sanitized sort of way. And in light of Menzel's growing fan base, it could be a hit. If you go:“If/Then” plays an open run at the Richard Rodgers Theatre. 226 W. 46th St., ticketmaster.com. By MATT WINDMAN. amNewYork theater critic Matt Windman is the theater critic at amNewYork, which means he sees a show virtually every night of his life. They tend to vary in quality. He is also a lawyer. Share on Facebook Share on Twitter Comments We're revamping our Comments section. Learn more and share your input.