'Shameless': Watch a Preview of Sunday Night's Episode

Another new episode of Shameless airs tonight, with the Gallaghers once again finding themselves in a mess. In "F**k Paying It Forward," Frank (William H. Macy) finds himself surprisingly popular with other parents.

In the fourth episode of season eight, Fiona (Emmy Rossum) gets a blast from the past that changes her view on life. Meanwhile, Frank decides to get involved at Liam's (Christian Isiah) school by joining the PTA. In the preview, he helps out with the car wash and attracts the attention of at least one mother.

Elsewhere, Lip (Jeremy Allen White) learns that sex might be harder to come by when he's sober. Ian (Cameron Monaghan) gets into a feud with a kid at the youth center.

Lastly, Kev (Steve Howey) and V (Shanola Hampton) try to find Kev's birth parents.

The new episode also includes an appearance from Dermot Mulroney, who plays Sean Pierce. The last time we saw him was in season six, when he almost married Fiona. He skipped town after a heroin relapse.

A second clip from the new episode previewed Mulroney's surprising return to the series. In the scene, Fiona storms past Sean. Debbie walks out with her, and stops to ask Liam, "How many times have I told you not to answer the door for douchebags?"

New episodes of Shameless air on Showtime on 9 p.m. ET Sundays.


Photo: Michael Desmond/SHOWTIME