There’s a moment in Tender Napalm – one of many – when your stomach clenches, and the friend I came along with droped all pretensions and had to clutch my hand for support. This is the typical effect of Ridley’s writing, but this play especially is an exquisite example of poetry in motion.

Tender Napalm returns to the Southwark Playhouse after its premiere last year, a triumphant example of this wordsmith’s uniquely compelling style. Ridley’s oxymoronic title embodies his play perfectly. Visceral descriptions conjure a colourful world at war that his characters have created, in order to escape reality and pain. This bittersweet contrast takes you upon a rollercoaster ride (the only way to travel in Ridley’s world) until the cast can take no more and must face the truth. The audience teeter upon the glittering knife’s edge which is the weapon of truth. The characters throw these knives – and themselves – back and forth in an elliptical battle. Ridley reveals the layers of this relationship as if delicately peeling back raw skin, but never mentioning the unspoken trauma which haunts their every word.

Lara Rossi and Tom Byam Shaw play this couple to every extreme: like the most intimate of lovers and hateful of enemies. They attack Tender Napalm like Olympic athletes, until sweat drips like tears on the floor.  William Reynold’s set is a bare, traverse stage, exposing that the kaleidoscopic setting the actors lead us through only exists in their minds. But boy, do they believe in it, exploring it with every inch of their being. Through Tom Godwin’s movement direction, imagination becomes a tactile space. Hurtling around the stage, I can see Shaw is soaked in blood, battling his way out of the belly of a serpent, or riding a unicorn through the wilderness. Tender Napalm is dependent on the actors investing everything into their characters; Rossi and Shaw do this and more. The stories they tell with just their exaggerated bodies and subtle reactions showcases them to be energised, sensational actors.

Their chemistry is electric in the warzone. Man opens: “Your mouth… It’s such a… wet thing. I could squeeze a bullet between those lips”, and Woman gives as good as she gets all the way to the climax. Ridley’s vocabulary is the fuel for this fiery relationship, and Director David Mercatali takes this momentum and kicks it up a gear. But every vehicle has to stop to refuel, and it is the tender moments which complete this piece. Forty fathoms beneath the sea is a safe place where Man and Woman don’t fight. They “float and fade” as they forget, punctuated by a particularly haunting song from Nick Bicât. And haunting is the best way to describe Tender Napalm.

Mercatali’s direction strips the production, and Ridley strips the characters, creating an intensely revealing and consequently poignant play. The explosive and sexual physicality of Tender Napalm ingeniously focuses upon the tacit, as much as what’s going on onstage, charging the relationship between Man and Woman with an unknown force that makes you tremble.

Tender Napalm plays at the Southwark Playhouse until 23 June. For more information and tickets, see the Southwark Playhouse website. Image by Camila Greenway.