Sharks in the Chicago River? What to know after sightings reported at river dyeing

UNITED STATES, March 15 — As the 2026 river dye celebration wraps up, take another look at the moment the Chicago River transformed into its iconic bright green color. Are there sharks in the Chicago River or is the dye getting to you? That's a question many in the city may be asking after sightings of an animal highly unusual for the waters of the Chicago River were reported during the annual river dyeing event on Saturday.

A set of fins could be seen circling the emerald waters during the annual river dyeing event that took place at 10 a.m. on Saturday.

Fortunate for those who enjoy kayaking on the Chicago River, the fins were not those of real sharks. Instead, the "fins" were a "visual stunt" orchestrated by Netflix to promote the upcoming film "THRASH."

Starting at the south side of Columbus Drive and the river, the "surprise shark fins" swam up and down the main stretch of the river between 11:30 a.m. and 4 p.m., according to a Netflix spokesperson.

The movie, set to release April 10, centers on the aftermath of a Category 5 hurricane that decimates a coastal town and a subsequent storm surge that brings hungry sharks to the area. It was written and directed by Norwegian filmmaker Tommy Wirkola and stars Phoebe Dynevor of "Bridgerton" fame, Whitney Peak and Djimon Hounsou.

If you missed this year's river dye event, you can re-watch it below!