What’s Worth Watching: ‘Grey’s Anatomy’, ‘Mom’, ‘The 100’ and more for Thursday, May 19

Grey's Anatomy, Caterina Scorsone
Byron Cohen/ABC
GREY'S ANATOMY - "Family Affair" - Meredith and Maggie support Amelia on an important day; Jo reveals that she has been keeping secrets from Alex while Arizona and Callie deal with the impact of their custody arrangement. Meanwhile, Ben leaps into action to help a friend, on "Grey's Anatomy," THURSDAY, MAY 19 (8:00-9:00 p.m. EDT) on the ABC Television Network. (ABC/Byron Cohen) CATERINA SCORSONE

Grey’s Anatomy (8/7c, ABC): Still showing remarkable vital signs after 12 seasons, this signature Shonda Rhimes drama delivers a near-perfect season finale with just the right blend of emotion, trauma, romance and humor. Yes, you’ll want to strangle some of the neurotic characters before it’s all over, but thankfully we’re not left hanging with any one melodramatic subplot. The focus of the hour is on Amelia’s (Caterina Scorsone) wedding to Owen (Kevin McKidd), and Grey’s fans know that trips down the aisle are rarely without hesitations and complications: several psychological, at least one of them harrowingly medical. The episode also manages to resolve one of the season’s least compelling storylines in satisfying fashion, while setting up a potential new triangle in a way that will leave viewers smiling. And how many dramas, new or old, have pulled that off this year?

Mom (9/8c, CBS): One of TV’s strongest comedies ends its third season still rolling with life’s punches, as everyone rallies around Christy (Anna Faris), who’s shell-shocked when she realizes how much a legal education will cost her. They play her anxiety for laughs, including a terrific running gag about self-help clichés, but it’s a real and serious concern, rooted in a realism that helps Mom stand apart from most other sitcoms.

The 100 (9/8c, The CW): Another grueling season ends for a grim fantasy-adventure that rivals Game of Thrones in its unsparing zeal to subject its heroes to torment, torture and impossible choices. In the finale, an embattled and outnumbered Clarke (Eliza Taylor), Bellamy (Bob Morley), Octavia (Marie Avgeropoulos), Murphy (Richard Harmon) and precious few others take on the insidious artificial-intelligence known as Alie (Erica Cerra) in hopes of halting her Body Snatchers-like takeover of the human race. These characters are way overdue a win, and so are the emotionally exhausted viewers.

Inside Thursday TV: We’re back in the present tense on The CW’s time-tripping DC’s Legends of Tomorrow (8/7c), as Rip (Arthur Darvill) lets his team get back to what passes as normal, so they can decide whether to continue their journey. Given the show’s renewal, it’s not hard to guess their answer. … There’s an opportunity for beautiful music to be made on Fox’s Bones (8/7c) as the team investigates the murder of the leader of an a cappella college singing group, and suspects include real-life members of chart-topping Pentatonix. … NBC’s The Blacklist (9/8c) concludes a particularly traumatic third season with Red (James Spader) closing in on the fiend responsible for Liz’s death and the task force scrambling to save one of their own after another betrayal. In other news, Tom (Ryan Eggold) is getting his own spinoff next season: The Blacklist: Redemption, pairing him with his biological mom Scottie Hargrave (Famke Janssen). Because that’s what passes for network-TV innovation nowadays: cloning.