The Beast From 20,000 Fathoms (1953)

Near the Arctic Circle researchers detonate a nuclear device and unwittingly thaw a prehistoric beast frozen for millions of years. The monster leaves a path of destruction across eastern North America as it heads straight for New York City. When heavy artillery proves ineffective against the towering creature, scientist Tom Nesbitt (Paul Christian) concocts a radioactive formula to neutralize the beast -- and ace shot Cpl. Stone (Lee Van Cleef) will deliver it by grenade.