 As of the series finale, David Boreanaz (qv) is the only actor to  have appeared in every episode, David Boreanaz (qv) and  Christian Kane (qv) are the only actors to appear in both the  first and last episodes of the series and David Boreanaz (qv),  Charisma Carpenter (qv), Alexis Denisof (qv), Julie Benz (qv)  and J. August Richards (qv) are the only actors to have appeared  in every season.