When I think of the word “relentless,” I think of John McClane, the character that Bruce Willis plays in the Die Hard movies. The first movie in the series is about a group of terrorists who take over a skyscraper in Los Angeles. McClane is an off-duty police officer who happens to be visiting his estranged wife there and gets caught up in the hostage crisis. All the Die Hard movies follow a similar theme, with McClane overcoming a challenging circumstance every single time.