Young doctor Tamara Dadiani unexpectedly receives news of the death of her ex-husband, epidemiologist Ivan Balandin, in Madagascar. Despite the divorce, they remained good friends, so Tamara, without thinking twice, goes to the “red island” with the goal of getting to the bottom of the reasons for the death of a person dear to her. First they try to convince her that Ivan was selling drugs and was shot by his “accomplices,” then that he was killed by Islamic terrorists from Madagascar. Tamara understands that all this is a lie. She meets Kashmiri surgeon Tahir Dogra and learns that local residents are being decimated by an unknown disease, much like meningitis. However, the usual treatment in such cases does not help, and Tamara guesses that Ivan seems to have lost his life precisely for this reason...