The Independent Recommends: The Five Best Shows

Bridget Riley (Serpentine Gallery, London)

The classic Op period: paintings from the 1960s and 1970s, blazing and shifting in black, white and grey. To 30 Aug

Disasters of War (Imperial War Museum, London)

Three ages of European war through the etchings of Jacques Callot, Goya and Otto Dix: flashes of horror, mass executions and madness. To 26 Sept

Collage (Crane Kalman Gallery, London)

Everybody does it - Cubists, Constructivists, Surrealists, Abstracters, Popsters... Here, 50 works trace a history of cutting and pasting from Picasso to Rauschenberg. To 7 Sept

Gary Hume (Dean Gallery, Edinburgh )

Smooth as paint: Hume's new work has flat, filled-in shapes, sherbet colour combinations and images simplified to next to nothing. To 17 Oct

Notorious (MoMA, Oxford)

One hundred years after his birth, Alfred Hitchcock lives. Group show (right) looks at his legacy in art, most cunningly in the "Phoenix Tapes". To 3 Oct