Lions and Tigers and Bears, Oh My!

Leather coat? Check. Handful of stones? Ditto. A small child nearby? Yep. You are now ready to defend yourself against a hungry-looking mountain lion, and the authors of a new book are going to tell you exactly how. The fact that you'll probably never encounter this situation in real life doesn't matter. You're the ultimate stuntperson. The serene eye of a dire situation storm. Cool as the proverbial cucumber.

In theory, anyway.

''I just cried and ran,'' admits David Borgenicht, 31, author of the hit The Worst-Case Scenario Survival Handbook and subject of said lion sighting. ''It left me alone, thank God. I didn't know I was supposed to open my coat to make myself look bigger.''

Now, however, he and coauthor Joshua Piven, 28, can prevent future feral feline encounters from ending in tragedy. They can teach readers how to deliver a baby in a taxicab (even a breech birth!), leap from a motorcycle to a car, and wrestle an alligator — with one limb caught in its jaws. Worst-Case features 40 life-threatening situations paired with advice from experts. (Sample tip on how to jump from a bridge or cliff into a river: ''Enter the water feet first, and clench your buttocks together. If you do not, water may rush in and cause severe internal damage.'')

''It appeals to people who are actually afraid of this stuff and people who are desk jockeys who want to get in touch with their inner MacGyvers,'' says Borgenicht, who adds that the book was inspired more by ''bad '80s television'' than by any personal phobias. ''It really is the action hero's handbook.''

Literally. Cinematic manly man Bruce Willis recently purchased more than a dozen copies of Worst-Case at a Philadelphia bookstore. Better yet, it has gone to press eight times, with a desk calendar due in July and a sequel detailing frightful travel scenarios coming out next spring. Says Borgenicht, ''We just want everyone to be careful out there.''