Christmas is coming to Philadelphia, but teacher Amanda Pepper is having problems keeping the classroom seats filled as the holiday break approaches, let alone getting her students interested in the true meaning of the season. She teaches English at Philly Prep, a school where high school students prepare to go to college and their parents' money insures that they will get there. Amanda decides a project to feed the homeless may excite the kids and teach them about giving instead of receiving. She plans to have the kids cook the food and feed their fellow citizens. One parent, Alexander Clausen, has the money and power to take over the project, however, and he does so in fine style. A catered dinner at his mansion, elegant but unsuitable gifts, and a carefully selected group of homeless are arranged by Mr. Clausen, and Amanda only succeeds in getting her students to be unwilling servers.
The event arrives as do 65 homeless persons, members of the Clausen family, some society friends including Amanda's socialite friend Sasha Berg, and Alexander "Sandy" Clausen dressed as Santa Clause. Amanda is there with her students and other faculty. The only unwanted guest is a murderer. Mrs. Clausen is drunk, Santa's daughter (and Mandy's student) Laura is frightened out of her wits, and Laura and her brother Peter attempt to manage their mother in the midst of this fiasco. Amanda leaves as soon as decency permits, goes home to grade papers, and finds a disturbing essay by Laura. Amanda shares it with her on-and-off boyfriend, police detective C. K. Mackenzie, a smooth-talking Southerner who has her bewitched with his drawl and blue eyes. The disturbing news comes through that Alexander Clausen has died in a fire, and the whole world seems to know that his daughter has a history with fire. The rumor mill has consistently ground out stories about her burn scars, nightmares, and haunted essays. Amanda feels desperate to protect the girl from what she believes to be untruths. Laura compounds the problem by confessing to murdering her father, but her disraught mother and brother also confess. Mackenzie tries to tear down the confessions as school ends for Amanda and her students, and both she and Mackenzie contemplate Christmas plans that are unwanted and will keep them apart.
Amanda battles on against a cold and bad throat, Christmas shopping and other impossibilities, Philadelphia's city-in-winter gloom and hazards, and Mackenzie's obstinance in refusing to look beyond the Clausen family for the murderer. Amanda pushes him to check out the homeless, the caterers, the cab drivers, and a mystery man named Jacob--anyone associated with the ill-fated charity party. An ornamental object appears to have been the murder weapon with the fire as a cover-up. Irate neighbors, Laura's Aunt Alma, Laura's missing boyfriend, and calls from Amanda's mother describing her matchmaking plans for Amanda's holiday visit to Florida all muddy the picture for the detecting school teacher. Amanda agrees to a special mission for one of her mother's aging friends and learns that Laura has been left alone. She remedies the latter by having Laura stay with her, secretly hoping it will get her out of the trip to Florida. A journalist named Nick was profiling Alexander Clausen before the murder and is now eager to publish while the story is still fresh; he befriends Amanda, somewhat against her better judgment. Laura goes with Amanda to take a gift to the elderly friend Minna, but Minna's ramblings seem somehow connected to the Clausen tragedy. Friend and photographer Sasha prints out photos from the party to try to identify the mystery man Jacob, the missing murder weapon, and other possible suspects who may have slid under the radar with the party as cover.
With so many threads to unravel, Amanda has her hands full with the mystery, her troubled houseguest, and the pending Florida "vacation". Can she resolve the murder with or without Mackenzie's help? What other clues will surface, and which of the present clutch of clues will prove to be red herrings? Christmas is a time to have a little faith--especially in the improving sleuthing skills of a Philadelphia school teacher named Amanda Pepper.