The Four Sea Interludes, played with the curtain down in the opera house, are used during scene changes and serve to preface the action and link together the various scenes. Not only do they set the moods for the scenes to follow, but also reveal the conflicts and motivations of the various characters.

The first, Dawn, describes the sombre atmosphere of the little fishing village at daybreak as the men begin their day's work. The ominous sonorities suggest the harsh, continuing struggle of the villagers against the forbidding natural forces that shape their world. Dawn comprises only two musical elements: one, a bleak melody high in violins and flutes punctuated by swift arpeggios from harp, clarinet, and viola, like a sudden glint of sunlight off a grey wave; the other, slow, hard chords from the brass.

The second Interlude, Sunday Morning, portrays, with a certain sullen numbness, the call to worship on the day of rest. Church bells, large and small, echo through the town, heard at the outset as horn calls and rhythmic figures in the woodwind with a broad melody assigned to the low strings, embroidered with an elaborate figuration by the flute. This is followed by the third Interlude, Moonlight, which paints the scene of the village at night with music of troubled restlessness. The mood is lonely and brooding with a gradual build up in intensity.

The closing Storm describes not only the terrifying fury of the wind and waves crashing upon the shore, but also the tempest raging in Peter's troubled soul. The tumult slackens three times near the end of the movement veering into the storm in Grimes’ heart and mind, which sees nothing but loneliness and hopelessness. His introspection, like the lull before the end of a storm, is eventually swept away by the increasing fury of the elements.

Peter Grimes was first performed at Sadler's Wells Theatre on June 7th 1945. The opening night was a resounding success. Michael Kennedy, among others, was overwhelmed by the occasion, citing the premiere as “the most momentous event in British music since the presentation of Elgar's Enigma Variations in 1899”.