It follows a group of students at an elite international school in Prague who break into an indoor water park where they are stalked by a masked murderer.

Shortly after, a group of international students from an elite Prague school are graduating; among them are the American Sarah; the Scottish Mike; the English Frank; Kim, an Australian; Carmen, from Germany; Diego, from Argentina; and others.

Aware that a killer is loose, Sarah, Mike, Carmen, and Chris intercept Martin en route back to the weight room.

The group are unable to locate Greg, Frank, or Diego, and Martin finds that the lock picks and spare keys to the building have been removed; the phones have also been disconnected.

He goes ahead to dismantle a vent grate, after which Sarah, Mike, and Carmen follow; Chris stays behind, as they are unable to turn around and lift him from inside the duct.

Outside, she finds a security guard's corpse with a gun lying next to it, but before she can retrieve it, she is stabbed by the killer and thrown back into the filter chamber.

Inside, Sarah is confronted by Frank, who reveals himself to be the killer, motivated out of spite and jealousy over his failed romantic advances on each of the women.

[2] Film critic Jim Harper wrote: "With the basic material so derivative and stereotyped, The Pool wasn't going to be a classic, but might have lifted itself above the average.