When Grampa goes missing from Springfield Retirement Castle, Homer and Marge's attempts to find him uncover an untold past that includes a black singer (voiced by Anika Noni Rose) as a second wife and a job as a busboy with Marvin Hamlisch. Meanwhile, Lisa gets into online poker so she can get more money for a better education after Homer puts his injury settlement money in online gambling to fight back against corrupt banks.
!!Tropes
* StealthPun: The day Homer and Marge forgot to visit Abe was on a blue moon.