But don't be fooled - disaster and unsettling irregularities lurk at every turn.
This is narrative art in which the image draws the viewer into action- packed scenes teeming with life, from an imagination that has given itself free rein. Planes plummet to earth, nannies push their charges into lakes, women gleefully expose themselves, and couples copulate in the wings.
Orr is drawing on childhood memories filled with steam trains, tea rooms, days spent at the seaside and trips to the fun-fair, all of which are heavily overlaid with naughty schoolboy humour. His chaotic, overcrowded depictions of human interaction recall the work of William Hogarth, though Orr is indulgent towards his subjects and seems to accept them warts and all.
Born in Islington, London, in 1943, Orr is primarily a print-maker, although he also draws and paints. When he first turned to print-making, he says: "There began the outpouring of my views of a flawed and wonky world. I celebrated the disorganised through an organised medium."
His Happy Days drawing, with added, vibrant watercolour, is indeed a flawed and wonky world, in which subversion is rife. The colour and hectic movement of a fun-fair have all been captured, but there's little fun to be had. The back carriages on the roller-coaster have detached themselves from the track, flinging the passengers into the air; the merry-go-round is swirling at such a speed that the horses fly out horizontally, with one breaking free, hurtling off on a course of destruction, and a distant helter-skelter abandons its customers to the unfriendly waters of a lake where hire boats are at various stages of capsizing, except for one which holds an indifferent, copulating couple. A prostrate body lies, ignored, beside the shooting range.
However often you return to this work, it seems there is always something disturbing that you have previously missed.
The artist's best-selling work by far is what he calls his poo poster, which has sold more than 10,000 copies to date. It is an A to Z that has allowed him to indulge his scatological humour to the full: ant poo, bear smells, cat's nasties and so on. This is humour without the sting in the tail.
Happy Days, paintings, drawings and prints by Chris Orr, at Jill George Gallery, 38 Lexington Street, London W1 (0171-439 7343) until 16 April