Every 48 years, the inhabitants of the remote Indian state of Mizoram suffer a horrendous ordeal known locally as mautam. An indigenous species of bamboo, blanketing 30 percent of Mizoram's 8,100 square miles, blooms once every half-century, spurring an explosion in the rat population which feeds off the bamboo's fruit. The rats run amok, destroying crops and precipitating a crippling famine throughout Mizoram. NOVA follows this gripping tale of nature's capacity to engender human suffering, and investigates the botanical mystery of why the bamboo flowers with clockwork precision every half century.