At 10 minutes to showtime a week ago Tuesday night, Adrianne Cury, the actress playing Rosemary in Festival Theatre’s production of Picnic had not yet arrived at Austin Gardens. Stage manager Bob Behr kept calling until Cury’s husband answered her cellphone. His wife, he said, had been in a car accident while bicycling to the show and was in the emergency room. The Aug. 1 show had to be cancelled, and understudy Katherine Keberlein arrived within a half-hour to start learning Rosemary’s lines.

Cury is currently being treated for a severe leg injury at Loyola Medical Center in Maywood. “Details of the actual accident and her specific injuries have not been forthcoming,” Picnic director Kevin Theis wrote in an e-mail Thursday afternoon, “as Ms. Cury has made no public statement on the matter and … we are attempting not to intrude upon her at this point.”

Her injuries are not life-threatening, according to Theis, but Cury was in and out of surgery last week and the injury will “definitely” preclude her from returning to the show. “Frankly,” Theis said in an interview on Friday, “our only thought is of her recovery and resuming her career and getting back to health as soon as possible.”

“Adrianne … brought an unequalled positive energy to her work,” Theis wrote in the e-mail. “Those people who were lucky enough to see her performance as Rosemary in the play will attest to the luminous talent she brought to the role. Adrianne’s understudy, Katherine Keberlein, has stepped into the role … so in true theatre fashion, the show will go on.”

Theis praised Keberlein’s professionalism and formidable memorization skills. She was “off book” within 24 hours and ready to play Rosemary last Wednesday night-the day after she found out she would have to replace Cury-but that night’s thunderstorms prevented the cast from performing. The next night, however, the sky was clear and Keberlein went on.

“I personally wasn’t able to make it,” Theis said, “but from all accounts, she was letter-perfect. I can’t imagine more unfortunate circumstances to have to do it under, but she did manage to pull it off, and we’re enormously grateful she was able to do it as quickly as she did under such incredibly trying circumstances.”

After performing in Picnic on Thursday and Friday, Keberlein was back onstage Saturday, Sunday and Monday, playing Portia in Festival Theatre’s other production, Julius Caesar. Taking on the Picnic role will mean performing seven nights a week until both shows end Aug. 19.

“You’ll hear I’m just a little bit hoarse, after saying the [Picnic] lines so many times,” Keberlein said Friday afternoon, following her first performance as Rosemary. “After I got the call, I stayed up late that night and got as much of the lines and the scenes in as I could.”

What Theis called her “miraculous” overnight memorization of the script was in fact due to a carefully crafted “magic formula” Keberlein has developed over the past 4-5 years. “Just writing the lines out-I think I filled a full spiral notebook-and then I tape the cue lines and play the cue lines out loud,” she said. “Now, I will admit there was quite a bit of paraphrasing going on last night, but by [this week], I should have it pretty much perfect.”

The rehearsal process was likewise technically complicated but quick. “The next day, I was incredibly fortunate to have Bob Behr, the stage manager, working with me, and then one of the actors-Jack Hickey, the artistic director [of Festival Theatre]-made sure I knew all of the blocking,” Keberlein said. “And that night we were scheduled to do another performance, but that was the night of the thunderstorm, so I got a bit of a reprieve.”

A reprieve from acting onstage, that is; Keberlein and the rest of the Picnic actors stayed to run scenes. “They are an incredibly generous cast,” she said. “Rather than having a night off with the rain, they stayed for two hours and worked with me. I was pretty proud of how it went.”

Keberlein said she is “fortunate” to work as an independent contractor. “I don’t work 9 to 5, so I have the daytime to do the rest of my living!” she added, laughing. This day-job flexibility and her husband’s cooperation, she said, allow her to balance work with taking care of her 7-month-old daughter. Even with her new show-a-day schedule, Keberlein said, “I can’t imagine anything I would rather do than … be at the theater seven nights a week.”

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