"It's complicated" doesn't even begin to describe the tangled relationships on "The Affair." And things are about to get even knottier, as teased in the new full-length trailer for Season 4.

Helen (Maura Tierney) and her boyfriend Vic (Omar Metwally) have moved to California, and Helen's ex-husband Noah (Dominic West) has followed them there. And while he has a new love interest (Sanaa Lathan), he still casts a shadow on Helen.

"I finally have a new life. The only problem is, you're still in it," she says to Noah.

Meanwhile, Noah's former affair partner Alison (Ruth Wilson) has a hot new Marine boyfriend (Ramon Rodriguez). But it seems her ex-husband, Cole (Joshua Jackson), just can't quit her.

Of course, that doesn't sit well with his new wife, Luisa (Catalina Sandino Moreno). Not only is Cole still pining for Alison, he has sex with a new woman (Phoebe Tonkin).

And then there's what seems to be the season's central mystery — a woman goes missing. Is it Helen? Alison? Luisa? Someone else?

"The Affair" Season 4 premieres Sunday, June 17 at 9 p.m. on Showtime.