Staying at the Palmers' residence after putting the Gray Gang behind bars (see D040 The Gray Gang), the Phantom learns of Diana's attempt to be the first woman to swim across the choppy and treacherous Whirlpool Channel.

Meanwhile, a local gangster goads Dave Palmer into betting serious money on Diana's swim succeeding. Soon, a number of murder attempts of increasing deadliness and audacity take place, culminating in the Phantom's having to battle man eating sharks during Diana's record attempt...

Watch out for:

An unusually gullible Dave Palmer placing a colossal bet

A deadly radio-controlled speedboat

Sharks loose in the Whirlpool Channel