Complex sentence: When he sees that it has been wounded by a hunter, he gets his rifle, intending to shoot it over Jessica's anguished protests, but as she pleads with him not to do so, it disappears.
Split into simpler sentences: When he sees that it has been wounded by a hunter, he gets his rifle. John intends to shoot the animal against the protests of Jessica, but as she pleads for him not to do so, it disappears.