With the fifth lens in place, the Dragon Eye 2 unveils the apparent King of Dragons, and Fishlegs immediately knows what it is and where to find it.
An announcement leads Astrid to question her relationship with Hiccup. The Riders discover an Armorwing that has a Dragon Eye lens welded to its body.
The Riders race to the home of the true King of Dragons. But the Flyers are already there, and they soon come face to face with the legendary creature.
While hunting for gemstones needed to complete the Dragon Eye 2, Hiccup learns an old friend isn't who he seems. Dagur faces a bully from his past.
While visiting Wingmaiden Island, a baby Razorwhip bonds with Ruffnut, who suddenly finds herself trying her hand at being a Wingmaiden.
Hiccup grows wary when Gruffnut arrives on the twins' 19th birthday to administer a Thorston coming-of-age ritual involving three dangerous challenges.
Upset after learning his ancestors were Hunters who killed off Dramillions, Fishlegs sets out to see if he can find any of the dragon species left.
Stoick and Hiccup are led on a wild goose chase in search of willow bark for medicine, leaving Berk vulnerable to an enemy attack.
During a trip to Wingmaiden Island to find a Dragon Eye lens, Snotlout challenges Hiccup's leadership. On another island, an unlikely romance blooms.
Sandi Toksvig ventures Overseas to find out about who keeps their brothers in a cage, and much more. With Bill Bailey, Colin Lane, Desiree Burch and Alan Davies.
Rodrigo distracts himself from the Requiem as he dives deeper into coaching Hailey for her big gig. Gloria gets a visit from a famous composer, eager to premiere his latest piece with the NY Symphony, but Thomas thinks his knows of a better fit. Despite doctor's orders, Cynthia returns to playing with renewed vigor.
On a mission to talk to Mozart, Rodrigo visits an unusual classical music collector (Michael Emerson) who might have what he needs. Hailey gets an exciting conducting opportunity, but has to prove she is up for the challenge. Thomas discovers the missing ingredient for the Queens Phil and invites Cynthia along for the ride.
Hailey faces off against new peers at the Fukusoft Conducting Competition in Japan. Rodrigo meets a new composer who claims to know more about Mozart than he does. Gloria tries to eclipse Betty in her fight for Fukumoto's attention, and Thomas is reluctantly reunited with an old flame.
Andi is left confused when Jonah stops wearing the bracelet and tells her he doesn’t like labels. At her basketball game, Buffy finally gets what she has been hoping for.
As Rodrigo and Hailey navigate the status of their new relationship. She gives her Ensemble a fresh direction. Thomas steals Gloria away from work for some afternoon romance. And a world-renowned choreographer (John Cameron Mitchell) invites Rodrigo to collaborate on a new ballet.
The Pamunkey find a way to teach the Sharrows a lesson. And it means major heartache for Alice. Yeardley's tested when he tries to intervene.
After a disastrous night at the NY Symphony, Gloria finds herself in a PR whirlwind, having to re-secure a major donor. Rodrigo becomes fascinated with the ballet, while Hailey tries to make some professional connections without his help.
Curtis and Ella debate about taking in Nyla and her kids. Ella talks to Nyla about how her relationship is affecting her children.