Leonardo DiCaprio is coiled to spring as Danny Archer, a former mercenary from Zimbabwe, now in the business of smuggling conflict diamonds, so named because their sale is used to subsidize civil wars in Africa. Set in Sierra Leone in 1999, the film, crudely scripted by Charles Leavitt, links Danny with Solomon Vandy (Djimon Hounsou), a fisherman trying to save his family. Danny will help if Solomon leads him to a huge pink diamond he’s hidden and gets rid of nosy journalist Maddy Bowen (Jennifer Connelly). Actually, getting rid of the annoying Maddy is my idea, not Danny’s. It might have been a socko adventure if director Ed Zwick (The Last Samurai) didn’t insist on turning it into a message movie. DiCaprio is terrific, but he can’t save this lecture from the shame of using Africa as a vehicle for another white man’s redemption.