Dan Stevens leaves the high-ceilinged drama vacuum of Downton Abbey far behind in this delicious psychological action flick meets black comedy. He plays a kind of anti-Jason Bourne special ops soldier who arrives unannounced at the door of the grieving Peterson family, whose oldest son, Caleb, has been killed in action in Afghanistan.

Claiming that he served in the same unit, David tells the wary Petersons that Caleb wanted him to “check on y'all” and proceeds to take up an unassuming presence in the atmosphere of stilted sorrow. But director Adam Wingard (You’re Next) is setting us up - we may think we are about to watch a pained and worthy 21st century update on post-Vietnam War films like Coming Home but The Guest soon turns into something quite unexpected and terrifically entertaining.

David is a smooth-talking, charismatic young southern gent who ingratiates himself quickly into the fragile family dynamic, expediting work problems for the lame-brain, booze bag father, sorting out high school bullies for intelligent teen son, Luke, and exchanging meaningful glances with the seemingly gauche 20-year-old daughter Anna (a great Maika Monroe). Heck, he even helps mom around the house.

But David is not all that he seems and Wingard lets the truth emerge in a series of hugely enjoyable action sequences and hair-trigger moments of unpredictability from the devilishly handsome rogue soldier. Wingard's love of director John Carpenter is there in an artfully-dated soundtrack of EDM and gothy electro which recalls the Ryan Gosling vehicle Drive (In a nice touch, Anna makes compilation CDs). We are plonked straight back into the 1980s in tone and atmosphere but without losing any of the slickness and verve of a top-notch modern thriller.

It all builds to a climax that references Carpenter’s Halloween as well as making nods to The Terminator, wearing its influences with great style and sending up every convention of the genre with affection, humour and sly self-awareness.

Stevens’ portrayal of the charming young man turned dead-eyed killing machine is a career-making turn. Wingard calls The Guest “the culmination of a lifetime of genre deconstruction”; you just might call it the best slice of merry mayhem you’ll see at the cinema this year.

Alan Corr

Read RTÉ Ten's interview with Dan Stevens here.