It's an important time for John, as he introduces new arrivals Seatao and Shadow to original tigers Ron and Julie in the hope that they will mate. Mesmerising footage reveals the cats' violent mating rituals, and follows the subsequent pregnancies up to the moment of birth.
After the exciting birth of the cubs, John reveals that the hard part has only just begun. Following the cubs during their first days, he makes the sobering discovery that their lives can be cut cruelly short. Later he faces a tough decision - to save lives or to let nature run its course.
Excitement is in the air once again as Julie, John's favourite tiger, gives birth to a new litter. But one of the cubs is smaller than its siblings and, when Julie is seriously injured in combat with a fellow tigress, John must decide whether or not he should save the little cub.