To a man, the members of the LAPD homicide department were yawning with unaccustomed inactivity. Then everything happened at once - a cop killed by a hit-and-run driver; the questionable suicide of a young girl; and the victim (apparently) of a heart attack found in the clutter of her ''second-hand'' shop.

It was the last that led Lieutenant Luis Mendoza to the Celtic Hotel, where events moved swiftly and with about as much clarity as the Mad Hatter''s Tea Party. But, in this case, the tea party was lethal.

''A Luis Mendoza mystery means superlative suspense''