When you enter Surreal Encounters, the big summer show at the Scottish National Gallery of Modern Art, the first thing you see is the resource room (isn’t that normally at the end?) closely followed by 'Room 3'. Well, this is Surrealism, you didn’t expect it to make sense, did you?

It does take time to find your feet in this exhibition because the curators are trying to do two quite distinct things: to tell the story of four major collectors of Surrealist art, and to create a survey exhibition of the movement itself. They’re not helped by the fact that Surrealism is hardly linear, and that artists regularly joined, left and flirted with its margins.

One finds a room devoted to Gabrielle Keiller, a former golfing champion who married into the Keiller marmalade dynasty and left her important collection of surrealist art to National Galleries of Scotland when she died in 1995, next to one about the influence of Giorgio de Chirico and a corridor devoted to Dada. But in the three large interconnecting rooms on the ground floor of Modern One, Surreal Encounters really hits its stride.

Devoted to exploring the various directions the movement took in the 1930s, these galleries include major works by all the big hitters: Dali, Magritte, Picasso, Ernst, Tanguy. The Lobster Telephone and Mae West Lips Sofa are here (complete with Dali’s original sketches for it, on the back of an envelope), but it is the paintings which dazzle again and again. One realises, rather belatedly, that this is one of the most significant shows of Surrealist art mounted in Britain in recent times.

It’s densely packed, full of documentary material as well as art, with collectors as colourful as the artists they patronised. It’s also full of surprises, from major works rarely exhibited to lesser known names, and it reminds us how radical Surrealism was, rooted in the 1930s but still relevant in artistic terms today. One emerges from it all a little dazed, having been immersed in a strange and at times confusing world, but one which still has the power to dazzle and amaze.

Scottish National Gallery of Modern Art (Modern One), until Sun 11 Sep.