Girls Generation's Yoona and actor Lee Bum Soo are both considering roles in a new KBS drama "Prime Minister and I," but despite the age difference, they are not going to be playing father and daughter.

As this drama will be a remake of the musical film "The Sound of Music," Yoona, 23, is considering the role of the young governess originally played by Julie Andrews. Her character will be hired to tutor the children of the prime minister, who will be played by Lee Bum Soo, 43.

Her character is a young woman who has given up on her dreams of becoming a musical actress, so its only natural that her classes for the prime minister's children will include spirited singing lessons. Her charm and enthusiasm quickly wins over his children and eventually convinces the charismatic prime minister to fall in love with her.

And that would be a great story except that Lee Bum Soo is so much older than Yoona. When Julie Andrews and Christopher Plummer played the leading roles in "The Sound of Music," there was only a few years age difference between them. While Yoona is certainly up to the singing required by the part, the 20-year age difference has many netizens wondering if such casting would really work. Will there be any chemistry between them? Why couldn't they find a slightly older actress to play the part of the governess, one netizen wondered? But chemistry between actors can be a difficult thing to predict.

According to Lee Bum Soo's casting agency, HB Entertainment, he has received the offer but has not yet decided whether to take the role, as he is currently busy filming the movie, "God's Trick." The actor has appeared in dozens of films and several dramas, including "Iris 2," "Dr. Jin," "History of a Salaryman" and "Giant."

Although best known for being a member of "Girls Generation, Im Yoona also has some acting credits. Besides a couple of cameo roles and a supporting role, she had leading roles in "You Are My Destiny," "Cinderella Man," and "Love Rain."

The role may have been offered to her because "The Prime Minister and I" is being produced by SM C&C, a subsidiary company of SM Entertainment, which manages Yoona.

The drama will air in December following "Future Choice." Yoon Eun Kyung, who wrote the drama "Take Care of the Young Lady" and Kim Eun Hee, who wrote "Phantom" will write the screenplay.