Disco's Dead and so is Mo-Mo

The mystery surrounding the disappearance of mobster Mo-Mo Martine in Canada during the days of disco and polyester is finally solved when his body is found in a drum off the sapphire waters of Oahu.
An associate (local limb-breaker Harry the Hoarse) asks the pretty private investigators from the Triple Threat Investigation Agency - JJ, Rey, and Linda - to prove it wasn't his brother-in-law, Johnny B. He'd been accused back then but never arrested, and it certainly appears that he's the perp now. The trio finds itself embroiled in the most challenging, if not deadly, case yet!
Countless people - family, friends, foes - hated Mo-Mo. Anyone could have murdered him. Or was it a professional hit by the notorious, never-miss Death Angel? Is it possible!? The faceless, nameless assassin-for-hire is still plying his trade after all these years?
As bodies drop, the P.I.s begin to believe answers won't come from anyone they interview; they'll be found in mysterious photos dating back to Mo-Mo's disco days. They merely have to decipher what the people and backdrops in those photos are telling them-a tricky task indeed. Will they figure it out before more murders occur... perhaps theirs?