8 p.m. on 5, 8, ‘‘The Voice’’ – The hit singing competition series returns for Season 4 with a two-night premiere and two new celebrity mentors — Usher and Shakira, replacing Cee Lo Green and Christina Aguilera. Tonight’s episode is two hours, and Tuesday’s is one hour. The series will continue its two-night Monday/Tuesday schedule as it did last fall.

8 p.m. on (CW), ‘‘The Carrie Diaries’’ — Carrie (AnnaSophia Robb) jumps at the opportunity to assume Larissa’s (Freema Agyeman) identity, but she’s not so thrilled when Larissa’s behavior catches up with her. A day in Manhattan has Walt (Brendan Dooling) confronting the feelings he’s been struggling to hide. Sebastian and Maggie (Austin Butler, Katie Findlay) keep a secret from Carrie in the new episode ‘‘Identity Crisis.’’

9 p.m. on TRAV, ‘‘Bizarre Foods America’’ — Mention Baltimore and food in the same sentence, and most people will think of steamed crabs. Andrew Zimmern is not most people. Crabs are definitely on his menu in the new episode ‘‘Baltimore and Chesapeake Bay,’’ but so are such unusual dishes as barbecued muskrat, Korean blood sausage and grilled eel — and he learns all about preparing them as well as eating them.

10 p.m. on 7, ‘‘180 Days: A Year Inside an American High School’’ — This two-part special follows a tireless team of teachers and school leaders dealing with the usual antics of teenagers and the changing tides of a fast-moving administration that is responding to pressures from outside partners, politicians and forces in the community. The documentary sheds light on both the extraordinary challenges and opportunities that today’s public schools face. Part 2 airs Tuesday.

10:02 p.m. on 2, 9, ‘‘Castle’’ — Castle and Beckett (Nathan Fillion, Stana Katic) investigate the death of a man whose body is found inside an industrial cake mixer. The murder turns out to be connected to an Irish gang in Staten Island and a bar owner (Cara Buono) with whom Ryan (Seamus Dever) has a history dating back to his days in narcotics. He goes back under cover to solve the case, to his wife’s (Juliana Dever) dismay, in the new episode ‘‘The Wild Rover.’’