Just wanted to clear this up, all of Langley Park is in PG County.
Langley Park CDP, Maryland - Fact Sheet - American FactFinder and
Langley Park, Maryland - Wikipedia, the free encyclopedia. Since it's not incorporated, it doesn't have any specific city boundaries, but the Census Bureau considers the borders to roughly be University Blvd to the south, New Hampshire Ave to the west, Riggs Rd to the east, and the Anacostia Tributary Trail System to the north. The western border of Langley Park touches Montgomery County (Takoma Park and Silver Spring) but the whole area is within Prince George's and patrolled by the PG police department.
Also, Red Top Rd is in Chillum, not Takoma Park