(Caution: this story contains spoilers from Ray Donovan Season 4!)

Ray (Liev Schreiber) heads into Season 4 of Ray Donovan trying to change by going to therapy and confession, abstaining from alcohol as well as getting rehabilitative help from Hector (Cruz Cordova), a big-time boxer recruited by Father Romero (Leland Orser) to help Ray become anew. However, it's not long before Hector inadvertently becomes a problem himself. Hector has a big secret, one that comes to light thanks to the emergence of a mysterious woman we soon learn is his half-sister Marisol (Lisa Bonet).

<p>Lisa Bonet, <em>Ray Donovan</em></p><p>

Lisa Bonet, Ray Donovan

Marisol is super messy: a shifty, opportunist drug addict who right away gets Ray tangled up in a dangerous and illegal mission that has him drunk again and framing a cop. She's an intoxicating presence in that first episode, due largely to the enigmatic, alluring vibe Bonet radiates when and wherever she appears.

But with scant lines and an unclear explanation of her relevance, she's mostly confusing; even after Hector explains to Ray who she is and the secret she's holding, what she really wants and why she's arrived now remains vague. She's as inconsequential in the first episode as she is destructive, a combination that, at first, cancels itself out to feel like a lot of nothing.

By the second episode though, Marisol is back and a delight to watch, albeit for the wrong reasons. Ray Donovan fast becomes the Lisa Bonet Show with Messy Marisol proving to be a vulgar, drugged-up train wreck whose talents include making cheap sexual advances at everyone she sees and smoking what appears to be crack. It's fun to see Bonet descend into junkie-dom, but her lines (which won't go recapped here, because they'd spoil the secret) often seem contrived — a shallow depiction of a junkie who's more of a loose-lipped drunk saying asshat things to piss people off versus an addict escaping real, long-simmering anguish.

Although her dark secret and her threat to expose it makes fertile, juicy territory for the show to explore, the execution of it belies resonance and believability in points — like when Ray is dispatched to get her right before she goes on TV to spill the secret and is smoking crack in the show's green room. Ray pretty much shrugs off her crack smoking too, prompting us to wonder if crack is the new pot or if we just shouldn't take Marisol — and her story — too seriously.

Still, Ray's race to manage her before she causes more trouble is the most captivating story that frames the new season — even as he juggles his dad Mickey screwing up his exile, his fractured family, Abby having a (Paula Malcomson) medical nightmare and of, course, the repercussions of the Minassian shootout. That's because Marisol's shocking secret parallels one of Ray's own demons — the thing that caused him to murder Father Danny O'Connor (Michael Cristofer) — and Marisol seems determined to destroy her brother, and Ray in the process.

Ray Donovan Season 4 premieres Sunday June 26 at 9/8c on Showtime.

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