Heterotandem bicyclic peptide complexes

A heterotandem bicyclic peptide complex comprising:

• (a) a first peptide ligand which binds to a component present on a cancer cell;
• conjugated via a linker to
• (b) one or more second peptide ligands which bind to one or more components present on a natural killer (NK) cell;
• wherein each of said peptide ligands comprise a polypeptide comprising at least three reactive groups, separated by at least two loop sequences, and a molecular scaffold which forms covalent bonds with the reactive groups of the polypeptide such that at least two polypeptide loops are formed on the molecular scaffold.