When does Hawaii Five-0 return?

The series premiered on September 20, 2010, on CBS and aired on Mondays for its first three seasons. It is a reboot of the 1968–1980 series Hawaii Five-O (the original series had the letter "O" instead of the number "0" in its title). The series also exists in the same fictional universe as the NCIS franchise by way of a crossover event with NCIS: Los Angeles.
The Hawaii Five-0 Task Force is a small, specialized Hawaii Department of Public Safety special state police major crimes task force in Hawaii, headed by United States Navy SEAL Lieutenant Commander Steve McGarrett. The team is able to investigate crimes ranging from terrorism to kidnapping as well as murder and robberies.