An early outrider to this year's Norfolk and Norwich Festival, Submerged-Spaces is a series of video installations hosted at three city venues.

The works by American artists Bill Viola all invite the viewer to slow down, employing slow motion film and vary degrees of religious imagery to force a more meditative and concentrated engagement.

The main exhibition at the Sainsbury Centre's hosts four works: the large-scale Ascension, showing an outstretched figure slowly falling through water; the double-screen Surrender, showing two inverted figures plunging in to a pool, their features startlingly revealed to be in reflection; Four Hands, a tightly-focused study on four pairs of hands; and Catherine's Room, the most transparently religious work, shown across five screens.

The first satelite show is in the undercroft beneath the city's Memorial Gardens, a large space normally unnoticed and inaccesible by the public. Shown here is the Quintet of the Unseen, probably the least convincing piece both in terms of its content and its setting, boxed in to an anonymised room.

The final piece, Visitation, is shown in the crypt of the 14th century Carnary Chapel in the Cathedral Close. Here two women slowly emerge from a white noise of digital fog, through water, to a clear, colourful immediate presence, only to regress back to grainy monochrome.

Submerged-Spaces continues Tuesday-Sunday, 10am to 5pm, until July 29.