You are (most likely) working with UTF-16le text. Decode it. A convenient way for files:

# With LF<->CRLF conversion
open(my $fh, '<:raw:perlio:encoding(UTF-16le):crlf', $fn)
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# Without LF<->CRLF conversion
open(my $fh, '<:raw:perlio:encoding(UTF-16le)', $fn)
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