Prior to auditioning at TUTS, Riordan had never seen "Little Shop of Horrors" on stage or screen and was minimally familiar with the show. He is, however, a huge fan of horror and remembers renting B-movies "three at a time" at Blockbuster on Friday nights. To prepare for the present-day role, he watched recordings of the 1985 off-Broadway production of "Little Shop" but felt inspired to put his own spin on the role.

"Little Shop" follows Seymour, a meek florist's assistant who is in love with his co-worker Audrey. One day, Seymour finds an odd plant that looks like a venus flytrap and names it Audrey II. When Seymour accidentally pricks his finger on a thorn, he discovers the plant needs blood to survive. Audrey II grows to mammoth proportions and generates big business for the flower shop. A romance blooms between Seymour and Audrey. But Audrey II's deadly cravings soon threaten to destroy all of Seymour's dreams.