The upcoming film follows Ben (Gambon) and George (Molina), a couple who marry at a City Hall wedding in Manhattan after 28 years of being together, reports Collider.
Shortly after their honeymoon, the couple are faced with a financial issue when Ben is fired from his job as a choir director at a Catholic high school.
The pair are forced to move in separately with other people - a nephew and his family in Brooklyn, and two gay cops next door.
Love is Strange will start shooting in New York in the summer.
Gambon starred in last year's HBO axed show Luck. He is best known for his role as Professor Albus Dumbledore in the Harry Potter film franchise.
Molina can be heard next in the animated biopic Poe about the legendary writer Edgar Allan Poe.
Watch a trailer for Luck below: