Dom and String return to Dom's birthplace when Dom learns that his daughter has died of a drug overdose. After attending the funeral, they return to California where Dom is arrested on suspicion of murdering his ex-wife. String returns to the island to investigate the murder and learns that unsavory elements have begun taking over the seaside community where a casino is being developed. String finds himself pondering a burning question...does the casino's developer have something to do with the deaths of Dom's wife as well as his daughter?

A helicopter prototype that may rival Airwolf is stolen. String thinks his brother St. John is involved.