Katharine Mcphee broke down in tears on Thursday (31May12) after losing her beloved cat.

The Smash singer/actress flew into a panic when she realised little Harmony had gone missing and began sobbing as she searched frantically for the feline.

She took to her Twitter.com page to tell fans about her nightmare ordeal, writing, "I just had the worst 4 hours... lost my cat... searched for her, gave up hope, cried, regained hope, searched again, cried, searched again... Lost hope, cried again."

But the former American Idol runner-up refused to give up on finding her pet.

She adds, "Sun was going down & decided to look one more time & then found her! & cried again from pure joy and exhaustion. The End. Oh and then she scratched me on my stomach to thank me... love that damn cat Harmony."