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Boomerang fish is a recurring gag used by Muppet Show character Lew Zealand. The idea came about during a meeting in which writer Chris Langham was asked to come up with an idea for the worst vaudeville-style act possible. His idea: "Lew Zealand, Boomerang Fish Thrower." ^{[citation needed]}

As the name implies, a "boomerang fish" is one that returns to its owner after being thrown. As Lew explains it: "I throw the fish away, and it comes back to me!"

Other fish acts by Lew include his "fabulous singing fish," who performed a gurgly version of "You Light Up My Life" as Lew pressed on their heads -- a gentler, piscine version of Marvin Suggs' Muppaphone act.

Names for Lew's fish have included Kevin (from the taping of episode 524 as seen in Of Muppets and Men), Fred (the final version of episode 524), and Turk (episode 317). In The Muppets Celebrate Jim Henson, Lew revealed that the first fish he ever threw was named Connie Sue.