The Piano as prequel
The Piano, while being a tremendously good film, is still, effectively, the unofficial prequel to Jurassic Park. It features Sam Neill as Alisdair Stewart, the great-great grandfather of Dr. Alan Grant of Jurassic Park, also played by Neill. Neill's character is stationed on a remote jungle island that will eventually come to be known as Jurassic Park, always running off to something (the dinosaurs, of course!). He locks Ada in not because of Baines, but rather to protect her from the now-rampant dinosaurs. He builds a fence (what for? The dinos!). Simply put, it all adds up. I was worried during my viewing of the film that Neill would die at some point because of his villainous nature, but fortunately for the sake of the Jurassic Park series, he was able to survive. And by the way I don't expect credit for this.
An old photograph of Stewart:
His great-great grandson having apparently lost control years later: