Cyclic cell-penetrating peptides with one or more hydrophobic residues

1. A complex comprising a cargo moiety and a cyclic peptide, wherein at least one atom of the cyclic peptide or at least one lone pair of the cyclic peptide forms a bond to the cargo moiety; wherein the cargo moiety is one or more therapeutic moieties, one or more targeting moieties, or combinations thereof; and the cyclic peptide is selected from CPP 1-2, CPP 1-3, CPP 1-4, CPP 1-10, CPP 1-11, CPP 1-12, CPP 1-13, CPP 1-14, CPP 1-15, CPP 1-16, CPP 1-17, CPP 1-18, CPP 1-19, CPP 1-20, CPP 1-21, CPP 1-22, CPP 1-23, CPP 1-24, and CPP 1-25.