Watch The Simpsons season 27 premiere online: Homer and Marge 'separate' as Lena Dunham guest stars

After being together for 26 seasons, Marge and Homer will legally "separate" in the premiere episode of The Simpsons season 27. During the separation, Homer starts to date a woman in her 20s. Episode 1 is titled, Every Man's Dream, and will air this Sunday 27 September at 6pm ET/PT on the Fox Network.

The official synopsis of the episode reads as follows:

Homer is diagnosed with narcolepsy, but instead of returning home with his prescription medication, he returns home drunk. He and Marge visit a marriage counselor and have a trial separation, during which Homer begins dating a 20-something in the all-new "Every Man's Dream" Season 27 premiere episode of The Simpsons.

Click here to watch the episode online on Fox's official website.

Meanwhile, in the premiere episode, Homer will fall for Candace, a pharmacist, voiced by Girls star Lena Dunham, and her co-actors Allison Williams, Zosia Mamet and Jemima Kirke will also lend their voices in guest appearances.

The Simpsons executive producer Al Jean in an interview with Entertainment Weekly cleared the air around Homer and Marge's divorce rumours and clarified that couple would "legally separate". He explained "I never said they were getting divorced. I never used that word. And the next thing I know, it's crazy headlines. I wasn't trying to trick people ... Cartoon characters can fall down cliffs or blow each other's heads off, but they cannot get divorced."

Talking about Homer falling for Candace Jean said, "Homer discovers that he has narcolepsy and he gets a prescription and they become interested in each other. She is forward and funny and interested in people who have big bags of prescription drugs."