People perform poorly at sighting missing and wanted persons in simulated searches due to attention and face recognition failures. We manipulated participants' expectations of encountering a target person and the within-person variability of the targets' photographs studied in a laboratory-based and a field-based prospective person memory task. We hypothesized that within-person variability and expectations of encounter would impact prospective person memory performance, and that expectations would interact with within-person variability to mitigate the effect of variability. Surprisingly, low within-person variability resulted in better performance on the search task than high within-person variability in Experiment one possibly due to the study-test images being rated as more similar in the low variability condition. We found the expected effect of high variability producing more hits for the target whose study-test images were equally similar across variability conditions. There was no effect of variability in Experiment two. Expectations affected performance only in the field-based study (Experiment two), possibly because performance is typically poor in field-based studies. Our research demonstrates some nuance to the effect of within-person variability on search performance and extends existing research demonstrating expectations affect search performance.