Lyle Kessler’s moving tale of abandonment, fear and isolation is brought vividly and movingly to life by Dilated Theatre at Southwark Playhouse this month.

Orphans is the story of Philip and Treat, two brothers who, having lost their mother before they can remember, are latterly deserted by their father and left to fend for themselves in a dilapidated apartment located in Kessler’s native Philadelphia.

“Man-child” Philip has seemingly never ventured outside. He is thwarted, controlled and stunted in intelligence, worldliness and any form of growth by his older brother Treat, the violent pickpocket breadwinner, who is terrified of any kind of external influence threatening the closeted, unhealthy and controlled way of life he has fostered for his younger sibling.

Chris Pybus pitches Philip perfectly, creating a wide-eyed, curious creature with a painful under-nourished look about him, exuding curiosity and longing for something beyond his four walls, whether this be remnants and reminders of the departed mother he barely remembers, books to read or permission to look out of the window. His frightened animal energy is both pitiful and endearing and the dynamic between him and older brother Treat, portrayed by a brooding, fiery Alexander Neal, is electrifying from the outset. Treat is not the easiest of roles, with the actor needing to marry his bubbling, pent-up anger with the vulnerable abandoned child inside, however Neal handles these nuances well and his outbursts of rage are believable and, at times, quite terrifying.

It was always going to take something unusual to upset and challenge this comfortable, carefully cultivated status quo and this comes in the shape of Harold, a drunk businessman Treat encounters in a bar, lures back to the apartment, and retrospectively decides to kidnap in the hope of raising some ransom money.

However, there is far more to Harold than meets the eye, and as events unfold, we see him gradually and manipulatively turn the tables by befriending Philip, moving into the apartment and offering Treat a “job”. His true agenda is never really revealed but the way he is able to shape the brothers’ perception of him with his kindred spirit, generosity, kindness (feigned or not) and ability to furnish them with a new-found sense of belonging and self-worth is quite ingenious. The shabby apartment becomes a home; they suddenly have new clothes, new shoes, decent food on the table. He is a father, mentor and employer all rolled into one, giving Treat the sense of worth and purpose he has been craving, flattering him into submission and allowing Philip freedom whilst simultaneously grounding him, opening his eyes and demonstrating to him his place in the world.

Genuine American Mitchell Mullen is perfect as the older man, from his entrance as the futile drunk to his final moments. He exudes a charismatic air of mystery which is perfect for the role and we never once doubt his ability to play Treat and Philip, controlling everything but the ultimate outcome of the piece which brings the world crashing down around the brothers’ ears all over again. The final scene is beautifully acted and downright heart-breaking.

Kessler’s excellent, thought-provoking script combined with some fabulous performances and emotionally raw moments make for a great night out on the Fringe. It would be fabulous if this could transfer; the play and actors alike deserve more exposure.

At Southwark Playhouse until 5 March 2016.