Recurring Guest Characters Vaughn Hillyard 6 guest appearances Guest Co-Host 6 guest appearances Guest Host 5 guest appearances Lisa Rubin 4 guest appearances Guest Co-Host 4 guest appearances Richard Engel 3 guest appearances Guest Host 3 guest appearances Andrew Weissmann 3 guest appearances Catherine A. Christian 3 guest appearances Yasmin Vossoughian 3 guest appearances Guest Host 3 guest appearances David M. Drucker 2 guest appearances Shaq Brewster 2 guest appearances Ali Vitali 2 guest appearances Aaron Gilchrist 2 guest appearances Danny Cevallos 2 guest appearances Barbara McQuade 2 guest appearances Guest Host 1 guest appearances Guest Host 1 guest appearances Peter Baker 1 guest appearances ⇤ « 1 2 3 » ⇥