Mike Faist has been playing the role of Connor Murphy in Dear Evan Hansen since the show’s earliest incarnation. He originated the role in the musical’s regional premiere at Arena Stage, starred in the sold-out Off-Broadway run, and is currently reprising his performance in the Broadway engagement at the Music Box Theatre.

Spoiler alert: Connor Murphy, a high school student, dies in the show; Dear Evan Hansen follows the chain of events sparked by his suicide. His tragic death forever changes the lives of his family and fellow students, particularly Evan Hansen, played by Ben Platt.

During his appearance on the AOL Build Series March 30, Faist told the host that there was a “huge shift in who Connor was” just before the world premiere in D.C.

Faist said that he had been working on the show with book writer Steven Levenson, songwriters Benj Pasek and Justin Paul, and director Michael Greif for a year and a half already before they decided to change his character as well as his relationship to the title character, Evan.

In the final version of Dear Evan Hansen, Connor continues to be a presence in Evan’s life after his suicide. Faist explained that in earlier versions of the musical, Connor didn’t reappear throughout the show after his death and had much less time onstage with Evan. It was a major development in his character.

“I was struggling to figure out who this new Connor was,” Faist admitted. “It was daunting… It was a real learning curve.”

Though daunting, the changes in the script gave Faist the opportunity to do some more research into his character and some of the complex issues that the show was now delving into—namely, suicide and mental health disorders.

“The biggest thing that I had learned was that there is a taboo [around] people with mental health disorders,” said Faist. “We want to glaze over it… It’s something that’s really important, and I think [the creators] have done a beautiful job [in exploring it].”

Dear Evan Hansen, which opened to positive reviews on Broadway this winter, is currently selling tickets through early 2018. Faist will continue to play Connor on Broadway through the fall, and says that the original cast will stay in the show through November.

Read More: WHAT DOES BEN PLATT’S DEAR EVAN HANSEN STANDBY DO WHEN HE’S NOT ONSTAGE?