theatre The Illusion Royal Exchange, Manchester

How can it be, marvelled Henry James, that the characters in fiction can matter so much? Corneille's 1634 comedy The Illusion is an extended play upon the phenomenon of an audience's investment of thought and emotion in figments, though the way that it is framed brings an especially demanding inflection to our awareness of the game that is being played. This adaptation by Tony Kushner renders the play's action and point in an immediately accessible version that nevertheless keeps entirely to the 17th-century milieu.

Pridamant comes to the magus Alcandre in the hope of making contact with his son Clindor whom he banished 10 years before. As Pridamant "watches gluttonously", Alcandre is effortlessly able to animate the vicissitudes of Clindor's subsequent life. Alcandre is, of course, the theatrical creator, conjuring beings of flesh and blood out of the void - and the emptiness of the unimagined world, vitally but precariously peopled by the brightly coloured, fluttering characters, is strongly evoked by the black disc and surrounding shadow of Stephen Brimson Lewis's design.

But the extra torque in Corneille's theatrical mechanism is that, as we watch a fictional character, Pridamant, he is watching his own son - quite a different dimension of empathy. Trevor Baxter's portrayal travels between jovial, that's-my-boy delight, to silvery disapproval and, eventually, despair. It is a fine performance that shows us the stiff neck, the blindness and the awkward tenderness of paternity. It is an irony, too, that the patriarch is himself rendered nearly child-like by the mastery of Richard Moore's commanding Alcandre, who does everything to illuminate, and finally reassure him, except effect an actual meeting between father and son. This is the comedy's most unsettling absence and one which points to its deeper questioning of the existence of reality.

On the other side of the play's door of perception, Clindor's adventures fall within the fictional stereotypes of the martial and the amatory. Here, Corneille seems to be satirising, especially in the poltroonish chevalier Matamore (Ian Bartholomew), the roles which will have serious import in Le Cid and his later tragedies. In both modes, the element of role-play is prominent. Yet Peter de Jersey as Clindor and Julia Sawalha as his (some of the time) beloved Isabelle, breathe energy and individual distinction into their parts. .

Kushner loads more metaphor into his text than is Corneille's habit, but he produces an entirely plausible and exceptionally vivid text that is given generous and intelligent voice throughout Matthew Lloyd's excellent production. As the "dogsbody" gently blows out the lights, we depart reluctantly into our own illusions.

To 5 July. Booking: 0161-833 9833

Jeffrey Wainwright