Murder-mystery thriller ‘Clean Sweep’ is an elaborate puzzle

The one consistent element that I appreciate in British thrillers across all genres is their knack of getting right to the point, sometimes in the opening scene — then toggling back and forth to fill in the contextual blanks and simultaneously move the action forward.

“Clean Sweep,” a new Irish thriller starring Charlene McKenna, fits snugly into this niche: it offers a compelling, elaborate-puzzle murder mystery that will keep you guessing all the way through to the end of its sixth and final episode.

McKenna stars as Shelly Mohan, a married-and-harried mother of three dealing with a teenage stepson, Derek (Rhys Mannion), daughter Caitlin (Katelyn Rose Downey) and younger son Niall (Aidan McCann), a bright kid who’s seriously ill and gets bullied on the school bus.

Shelly and her husband, police detective Jason Mohan (Barry Ward), are going through a rough patch both financially (overextended) and in their marriage — he’s loving enough at home, but she suspects he’s having an affair with Fiona (Jeanne Nicole Ni Áinle), his partner on the force.

The series opens with Shelly scrubbing blood from her clothes. Flash back to nine hours earlier when, in the midst of her typically hectic day — PTA meeting, schlepping the kids around, preparing dinner — she’s approached in the local market by a bearded man with a bad mullet named Charlie (Adam Fergus). They know each other and she’s shocked to see him; he asks Shelly — he calls her Maggie — to meet him at his hotel room later that day. She arrives, wearing a disguise, and he greets her effusively, showing her a decades-old photo of them (and another man) posing together (she’s pregnant) and looking happy. They argue and, when he implores her to stay, Shelly/Maggie shoots Charlie twice — killing him and fleeing the scene as he bleeds out on the carpet.

As the story arc progresses, Jason and Fiona are tasked with solving Charlie’s murder — he’s identified as Philip Whelan, a low-level English drug dealer suspected in a gangland killing who disappeared 20 years earlier and was presumed dead. His brother is politician Rory Lynch, who’s up for election. As Jason and Fiona get closer to uncovering the murderer, including CCTV footage of Shelly and Charlie in the supermarket, she desperately tries to eradicate mounting incriminating evidence — including that aforementioned photo: Shelly thought she destroyed it by ripping it up, but Caitlin found it in the garbage and taped it back together.

Yikes.

“Clean Sweep” will keep you guessing at every turn, particularly when it kicks into high gear and Shelly/Maggie’s checkered background is revealed and the clock ticks as the murder case against her intensifies. Pay attention to details that might seem inconsequential — a tattoo, the contents of a safety deposit box, quick-cut scenes flashing back to Shelly’s childhood … they all factor into an edge-of-your-seat thriller that leaves open the possibility of a second season.

I’ll be watching.

“Clean Sweep” premieres June 22 on Sundance Now and AMC+.