^M was the carriage return as described previously thanks to everyone.
I was editing it in UltraEdit because I can never get to grips with vi editor - I know that's blasphemy! - but UltraEdit is so...
I have a script in a directory -say users/me/test/
It looks like this:
# "bkup" - copies specified files to the user's ~/Backup
# directory after checking for name conflicts.
a=$(date +%T)
cp...