  We search through $\gamma$-ray data obtained with the Large Area Telescope
(LAT) onboard the Fermi Gamma-Ray Space Telescope and find 24 blazars (or
candidates) that have a single clear flare event in their 9.5 year long-term
light curves. We define these events as loner flares since each flare stands
out significantly above the relatively stable, low-flux light curve. We analyze
the LAT data in detail for these 24 sources. The flares in ten of them are
primarily due to a single sharp peak, for which we study by fitting with two
different analytic functions. The time durations thus determined for the sharp
peaks are in a range of 4-25 days. The $\gamma$-ray spectra of the 24 blazar
sources can be described with a power-law or a log-parabola function. We obtain
their spectral properties in the flaring and quiescent states, and find that in
the flares 16 of the sources have harder emission and three have softer
emission while the other five keep the same emission. We discuss a possible
correlation between the differences in photon index in the quiescent and
flaring states and photon indices in quiescence. In addition, the sharp peak
flares seem to have a tendency of having long time durations and hard emission,
possibly related to their physical origin in a blazar jet. Studies of more
similar flares will help establish these possible features.
