The stories all centre around the M.A.S.K. organisation led by the fearless Matt Tracker. M.A.S.K. agents wear helmets or masks to protect their identities and to give them super powers which help in their fight against the criminal V.E.N.O.M. organisation. They drive super powered vehicles which can transform.
V.E.N.O.M., aka the Vicious Evil Network of Mayhem, are the bad guys. They are by Miles Mayhem one time friend of Matt and co-founder of MASK who betrayed Matt long ago.