PJ, a great bowler himself, hopes to enter a professional tournament to earn money for a favorite charity, but being only 14, he’s sure the directors won’t permit it. He and his friends hatch a scheme. PJ wears a mask, explaining that he’s a secret government mob witness and must use an alias (Señor Mysterioso) and hide his identity. Being tall, the mask does the trick. Unexpectedly, news stories of this brave masked bowler appear everywhere. Mob bosses in several cities, each awaiting his own trial, individually sees a picture of this masked Senor - and believing him to be a secret trial witness against him, sends thugs to the tournament to prevent Mysterioso from testifying. With mobsters from all over descending on the tournament, bedlam follows - with wild fights, shootings and kidnappings galore. Meanwhile, PJ is trying to win the tournament against some of the toughest and sneakiest competitors one can imagine.