Deadly Essence is the second book of A Murder in the Kitchen series where the story continues with Marty who journeys from the Hawaiian shores of Maui to Coastal Southern France in search of more than just new business opportunities. Through her exploits and a subconscious desire of self-discovery, she finds herself in precarious situations, as if trouble seems to follow her wherever she goes.
At a chef awards show, Marty meets two women chefs who invite her to their restaurant. Friendships do not always begin for the same reasons, as Marty is taken captive and held for ransom by the two chefs. They take her to a private island and is left in the hands of a cohort who has multi-personalities.
In the meantime, Marty's husband, John hires a private detective to help secure Marty's release, yet Marty manages to escape the island after two of her captives fortuitously die. Marty is subsequently charged with murdering them and goes on the run. Ultimately, she flees France on a Portuguese cargo ship as a cook. While on the ship she is accosted by a few of the crew members. She takes revenge by poisoning each member of the ship and then sinking it.
She winds up in New Orleans where the surviving captor tracks her down. Marty falls prey to the captor who gets Marty hooked on opiumit's a ploy. Enter John and the private detective to save the day. But, as a result of Marty going over a psychological cliff with being held captive and drugged, Marty slips into a schizophrenic state.