Guest Stars Jeff Perry as Thatcher Grey Rachael Taylor as Dr. Lucy Fields Alexa Havins as Danielle Co Starring John O'Brien as Lab Tech Jeffrey Cici Lau as Trial Partner #1 Shelli Boone as Paula Glass Aixa Clemente as Trial Partner #2 Desean Terry as Colin Cooke Noah Schuffman as Randy Roberta Bassin as Trial Patient #4 Edythe Davis as Trial Partner #4 Steven Anders as Trial Partner #3 Karen Tarleton as Trial Patient #2 Patricia Forte as Mrs. Glass Cathrine Grace as Trial Patient #6 Ken Takemoto as Trial Patient #1 Tracey Aileen Leigh as Sarah Cooke Darius Dudley as Trial Patient #3 Duane R. Shepard, Sr. as Trial Patient #5 Michael Esparza as Marcus