They were cruising for a bruising. Passengers freaked out as 40-foot waves slammed into a cruise liner navigating a treacherous stretch of ocean off Antarctica, as seen in freaky footage on Instagram.

Passengers aboard a luxury cruise ship had a harrowing experience as 40-foot waves battered their vessel while crossing the Drake Passage — the notorious 600-mile-wide stretch of water separating Antarctica from the southern tip of South America.

Passengers on Quark Expeditions' Ocean Explorer ship got rocked with waves up to 40 feet on a recent cruise, rocking those onboard.