fans have created an entire universe based on the productions in which Hugh Dancy and Mads Mikkelsen starred

a convention dedicated to Hannibal takes place in London every year

Mads and Hugh are still friends

Mads and Hugh have been touring conventions since last year. The events sell out every time. It also happened thay they got the main convention hall, and even then, the event sold out

in the US, at their first convention together in years, the organizers had to extend the photoshooting hours of Mads and Hugh because they didn't expect such interest

Mads skipped the world premiere of the film he was starring in to fly to Japan with Hugh

in Japan, there was a special dinner as part of the convention (expensive). It sold out pretty fast

we randomly receive madancy photos every few years

fanart from the series hangs (or was hanging) in the United States Capitol (a government building!)

academic articles about the series are being written

fans often publish zines

a tons of fanfics and fanarts are still being created

[EDIT, because I have no idea how I dare to forgot] Fannibals also created a freakin' musical with their own songs and drawings (season 1-season 4)