On tonight's 30 Rock season 3 finale - "Kidney Now!" - Jack's (Alec Baldwin) will try to connect with his biological father (guest star Alan Alda) but his health hangs in the balance just as they start to build a relationship. Meanwhile, Liz (Tina Fey) starts to gain a reputation for being a relationship expert after an appearance on a talk show, despite her own many failed relationships. As for Tracy (Tracy Morgan), he is invited to speak at his old high school during graduation, and Kenneth helps him overcome some embarrassing moments from those turbulent years.
The season 3 finale of 30 Rock will feature Sherri Shepherd, Sheryl Crow, Mary J. Blige, Elvis Costello, Clay Aiken, Maroon 5 frontman Adam Levine, and other surprise musical guests. On one promo, Aiken, Costello, and Blige are being blackmailed by Jack to do a concert for Jack's father. On the last episode of the NBC comedy, Liz concocted a Mamma Mia-like scenario to help Jack find his father. Meanwhile, Tracy looked like he found his illegitimate son, but Pete and Liz had something else in mind. Jenna reluctantly shared credit for a new TGS catchphrase with Liz.