Section 1008. Answer of third-party defendant; defenses

The third-party
  defendant shall answer the claim asserted against him by serving  copies
  of  his answer upon the third-party plaintiff. The third-party defendant
  may assert against the plaintiff in his answer any  defenses  which  the
  third-party  plaintiff  has  to the plaintiff's claim.   The third-party
  defendant shall have the rights of a party adverse to the other  parties
  in  the  action,  including  the right to counter-claim, cross-claim and
  appeal.