In my opinion, this movie's story is not all that interesting or original. As it's been said many times, To Have and Have Not is essentially Casablanca's twin sister, and bares almost no resemblance to the Ernest Hemingway novella. But despite it all, I must say that I prefer this movie as opposed to the other.
What makes this movie so good are three things: the writing, the acting, and the real-life chemistry between the supercouple of the time, Humphrey Bogart and Lauren Bacall. The screenplay has perhaps some of the most clever and memorable one-liners in movie history. In fact, this is the movie that produced the now-cliche saying "You do know how to whistle, don't you...just put your lips together, and blow," as well as the lesser-known but sure-to-bring-chills "It's even better when you help," sdaid after Bacall kisses Bogart. The acting is extremely good, especially since both the leads can be very cold and distant one moment, and very warm and sweet the next. Finally, as this movie will always be remembered for, Bogart and Bacall are clearly falling in love as the story is going, a case of art imitating life. The sexual tension in the beginning can be cut with a knife, while the true love in the middle and end is nothing short of romantic and touching.
To Have and Have Not is a quintissential example of the stars making a subpar story into one of the most romantic films of the era. This is the perfect start in exploring the world of Bogart and Bacall, and perhaps the best of their four films.