katherine mcphee plays the tough way tret and mom of a 9-year-old she believes is mentally challenged who's about to lose. >> i was kathrcat kakt rinne. >> what was it? >> going from singing and dancing to acting sequences where you're doing green screen stuff. that's a nice change. >> her last show with nbc's "smash" which did not live up to its name. it was cancelled after two seasons. a tough blow for mcphee who if she had it her way, she would sing all day. >> even my parent when we went skiing, they'd pass by me and i was singing, a way to calm myself. i think the singing is with me everywhere i go. >> mcphee was just 21 when america first heard her voice on "american idol." her fans called themselves the kat pack and said was fever. that's now how it felt for he. >> i was trying to survive. >> she was runner up to taylor hicks. you likely won't see a music number on "scorpion" be thaw won't silence her. >> i think everyone on the set will vouch for me. i never stop singing. i don't try to do it to be obnoxious. look at me. all kinds of stuff. it's out of control, really. i need

. >> katherine mcphee will be a guest on "live" with kelly and michael. i'm matt o'donnell.time at the library across town, where she connects with some of her biggest fans. when older pennsylvanians make the most of programs supported by the pennsylvania lottery, like free and reduced-fare shared rides, we all benefit. learn more at palottery.com. the pennsylvania lottery benefits older pennsylvanians every day. announcer: it's "live with kelly and michael." today, singer and actress katharine mcphee. from the new film "no good deed," taraji p. henson. plus, your question and comments direct from kelly and michael's inbox all next on "live." [captioning made possible by disney-abc domestic television] announcer: now here are kelly ripa and michael strahan! ♪ [cheers and applause]