Full spoilers follow for the season premiere of War.

HBO’s slick new legal drama War will almost certainly be its next big water-cooler show, and deservedly so, as it’s a sharply written, deftly paced, and well-acted trashy delight.

The Season 1 premiere quickly establishes rival London law firms Cathcarts & Sons and Taylor & Byrne and their respective clients: social media mogul Morgan Henderson (Dominic West) and his movie star wife Carla Duval (Sienna Miller). Their long, now loveless marriage is basically over. So that means a very expensive and very public divorce will inevitably follow.

Carla not only wants out of the marriage, but she also wants to take Morgan’s fortune with her. But their pre-nuptial agreement is designed to keep Morgan bulletproof — provided he has lived up to his end of their bargain. He hasn’t. He’s been unfaithful to her before but this time Carla is armed with photographic evidence thanks to a honey trap.

Carla assures her lawyers she didn’t enlist her younger actress friend to sleep with Morgan but that doesn’t ring true. Her lawyers Serena Byrne (Phoebe Fox) and Nicholas Taylor (James McArdle), partners in both the firm and romantically, don’t like Carla’s underhandedness as it could be bad optics. Carla wants to file for divorce first but she and Taylor & Byrne are unaware that Morgan and his lawyers at Cathcarts have already deduced that she’s poised to file.

Beatrice “Queen Bea” Ubosi (Nina Sosanya) and St John Smallwood (Pip Torrens), Serena and Nicholas’ counterparts at Cathcarts, fire the first shot in this war by serving Carla divorce papers on the red carpet at the premiere of her new movie, a savage move reminiscent of Olivia Wilde being served onstage at CinemaCon. And Carla then has to smile for the cameras with Morgan at her side?! Ouch.

The episode’s biggest surprise, however, is saved for when we learn that the ambitious, overconfident young lawyer Johnny Warren (Archie Renaux) – newly hired by Taylor & Byrne specifically to work on Carla’s divorce – is, in fact, a mole working for Cathcarts. For the entire episode, we follow Johnny’s desperate search for a job at a law firm, so the reveal that he’s going to be the show’s equivalent of Matt Damon in The Departed is a fun twist.

Still, as a scrappy, lower class guy trying to make his way up the social ladder, Johnny is sympathetic — for now. Like Charlie Sheen’s character in Wall Street, the question remains just how much of his soul he’s willing to sell to succeed and how many personal relationships Johnny may destroy in the process. It’s a testament to the writing and to Renaux’s nuanced performance that the viewer remains invested in Johnny even when his arrogance gets the better of him.

War is impeccably acted across the board by an ensemble cast filled with familiar UK character actors playing the respective firms’ legal teams. As for the leads, West finds some sad-sack sympathy in his tech bro mogul, while Miller imbues Carla with a steely resolve that suggests she’d have been a natural fit in the boardroom had she not pursued acting. They’re only in one sequence together this episode but it’s rife with tension.

Showrunner George Kay’s finely tuned script is as darkly funny as it is sad in its portrait of the wounded (if not outright lost) humanity of its many characters, people who may not want to be this nasty but, well, that’s what you’re paid for, luv. I can’t wait to see what these posh bastards do next.