Certificate: 15

Running Time: 132 mins

Star Rating: 4/5

ON the campaign trail, Republican presidential nominee Donald Trump promised to "drain the swamp" in Washington DC and restore integrity to American politics. The lead character of John Madden's riveting political thriller is one of those egregious pond-dwellers. Portrayed to icy perfection by two-time Oscar nominee Jessica Chastain, Elizabeth Sloane is a cut-throat lobbyist, who shrewdly anticipates her opponents' moves and devises cunning counter-measures as she manipulates the hearts and minds of power players on Capitol Hill.

A pill-popping insomniac, she's a delicious anti-heroine for a modern age of appearance-driven politics - someone to secretly root for as she unapologetically wrecks lives in her relentless pursuit of glory. First-time scriptwriter Jonathan Perera arms his crisply suited combatants with whip-smart dialogue for bruising verbal exchanges.

Elizabeth's current firm of Cole Kravitz & Waterman, headed by George Dupont (Sam Waterston), implores her to lobby against the contentious Heaton-Harris bill, which is poised to go before Congress and proposes more rigorous background checks for firearm purchases. She refuses and defects to rivals Peterson Wyatt, run by Rodolfo Schmidt (Mark Strong).

In modest, new surroundings, Elizabeth tests her reputation as a woman with a "gold medal in ethical limbo" by marshalling support for the bill. Her tactics reap rewards and, in retaliation, Dupont searches for evidence of illegal practices that will force his former golden girl to stand trial at a hearing chaired by Congressman Ron M Sperling (John Lithgow).

Miss Sloane unfolds largely in flashback in order to conceal scriptwriter Perera's sly plotting. Chastain is imperious, revealing tiny chinks in her character's polished armour as she teeters precariously on the precipice of self-annihilation.