In 1982, Walter Hill directed '48 Hrs.,' with Nick Nolte as a loose cannon cop and Eddie Murphy as a fast-talking criminal. The oil-and-water chemistry worked, the movie was a hit, and an entire genre -- the buddy cop movie -- was born. Hill has had a long a varied career in Hollywood, directing tough, lean action movies and Westerns and producing the 'Alien' franchise, but '48 Hrs.' and the myriad imitators it birthed will always be his biggest legacy. That fact alone makes his new movie, 'Bullet to the Head,' interesting, since it's Hill imitating himself, with his first return to the genre since 1990's 'Another 48 Hrs.' The mixed results probably won't inspire a resurgence of buddy cop movies, but they're not terrible either, with enough Walter Hill flair to make some moments quite memorable, even if the movie as a whole has its problems.