Peter Gallagher starred in The O.C.. The O.C. has genre Teen dramaThe O.C. is starring Tate DonovanTate Donovan starred in Good Night, and Good Luck
[Human]: Do you know Peter Gallagher? [Assistant]: Yes. He is an actor, starred in The O.C., While You Were Sleeping and many more. Are you a fan of him? [Human]: Yes I liked him in The O.C. Tate Donovan was also in that movie.  
That's right. Tate is really good in Good Night, and Good Luck too. Have you seen that movie?