Actor Morgan Freeman spoke on the Hill about a bill banning shark-fin sales. (Oceana)

Just in time for Shark Week, the marine creatures got a powerful advocate in actor Morgan Freeman, who came to Capitol Hill on Thursday to support bipartisan legislation banning the sale of shark fins.

What’s the “Invictus” star’s connection to the issue? Well, he happens to really dig sharks, okay? And he’s got a track record of environmental activism — and he hosted a documentary series “Through the Wormhole” on Science TV, which he says made him double down on conservation.

At a House-side news conference with several lawmakers and the advocacy group Oceana announcing a new bill, Freeman described “finning,” in which fins are cut from a still-living animal. “It is a very brutal practice — they hack the fins off … and dump it back into the sea, where it will drown or bleed to death or be eaten alive by other fish,” he said in his famously authoritative-yet-mellow “voice of God” tone. “It’s cruel. It’s wasteful.”

Finning is already illegal in the United States, but the Shark Fin Trade Elimination Act would cut off sales of the fins, which Freeman said perpetuates the practice.

He likened it to the killing of rhinos for their horns. “That’s supposed to be an aphrodisiac,” he said, to laughs from the crowd. “But shark fins? I still haven’t figured that one out.”