It's been promoted as one of the biggest events in television history.
Tonight at 8 p.m. on ABC, Marvel's Agents of S.H.I.E.L.D premieres. The show, set in the same universe as "The Avengers" follows S.H.I.E.L.D agent Phil Coulson and his team as they investigate extraordinaire cases.
On the Valley's FOX at 8:30 p.m., it's the second episode of Brooklyn Nine-Nine. The Comedy stars Andy Samberg as an immature, but brilliant detective.
Over on CBS The V, starting at 8 p.m. last seasons top three dramas, NCIS, NCIS: Los Angeles and Person of Interest all have their season premiers.
On NCIS, last years most watched show, Ziva's farewell begins as the character will be leaving the show during this season.