"Le Saviez-Vous ?"

Y'a pas de muguet dans BB.

Si y en a, enfin pas directement (le poison qui revient au fur et à mesure n'est pas du muguet mais de la ricine), mais y a bien une métaphore sur le poison du muguet.

When Walter White was contemplating how he was going to topple drug kingpin Gustavo Fring, he noticed the potted lilies in his backyard. ("End Times")

Brock Cantillo was poisoned by Walt in an unknown way with the Lily of the Valley berry. The doctors initially thought he was poisoned by ricin as Jesse Pinkman had suggested but later discovered the true toxin. The doctors and Jesse believed that Brock came across the flower growing naturally and ate some poisonous berries.