I dunno--these days if I were to see a guy hiding behind a tree with a camera or binoculars, I'd call 911, or take off running!
This card was from the era of the flappers, printed in the USA. It has movable parts. When the little red heart on the side of the card is moved, tiny metal rivets cause the little girl to peek from the water and the boy to pop up from behind the bushes. It was also made to stand upright by bending the flaps at the bottom of the card.