What to Watch Thursday: Elementary Brothers Unite, Burke's Back on Grey's, 3 Finales and More

Paint It BlackOn TV this Thursday: The iHeartRadio Music Awards are live from L.A., Grey’s Anatomy welcomes back Burke, Elementary gets personal and the Vikings have a showdown. As a supplement to TVLine’s original features (linked within), here are 10 programs to keep on your radar.

PHOTOS | The Vampire Diaries‘ Damon, Stefan and Caroline Make a Grim Discovery

8 pm iHeartRadio Music Awards (NBC) | The most popular artists and music over the past year — as determined by iHeartRadio listeners — will be honored at Los Angeles’ Shrine Auditorium.

8 pm The Big Bang Theory (CBS) | Bob Newhart returns as Professor Proton to help Sheldon cope with grief, while Amy and Bernadette make a “Star Wars Day” gift for the guys.

8:30 pm The Millers (CBS) | When Tom tells the family he’s dating a much younger woman, Nathan does some spying to make sure this lass isn’t a gold digger.

VIDEO | Grey’s Anatomy: Isaiah Washington Is Back — Watch Cristina and Burke’s Awkward Reunion
PREVIEW | Grey’s Anatomy‘s Caterina Scorsone: Will Amelia ‘Betray’ Addison By Joining Team Meredith?

9 pm Reign (The CW) | After enlisting a mercenary to help her, Mary realizes she is willing to sacrifice and risk lives to save her country.

9:30 pm Surviving Jack (Fox) | To get Rachel more involved in school, Jack gets her a spot on the wrestling team — much to the dismay of the coach (The Middle‘s Neil Flynn).

9:30 pm Bad Teacher (CBS) | Meredith wants to date a student’s wealthy father (Ken Marino, Childrens Hospital) but said pupil refuses to give her permission. 

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PREVIEW | Vikings: Will Floki Commit a Deadly Betrayal? Gustaf Skarsgård Teases ‘Jaw-Dropping’ Finale

10 pm Vikings (History) | Season finale: As Ragnar and King Horik return to Kattegat, the final showdown between two Viking leaders is at hand. (Already renewed!)

10 pm Elementary (CBS) | Sherlock is forced to partner with his estranged brother Mycroft to solve a life-or-death case.

10 pm Portlandia (IFC) | Season finale: Peter and Nance go on a walking tour; Toni and Candace lead a feminist retreat. (Already renewed!)

10 pm Sirens (USA Network) | Season finale: After a close call on the job, Theresa decides to join the FBI in Washington — prompting Johnny to propose marriage. (Not yet renewed; check status.)

Hit the comments with your must-see picks from tonight’s lineup!