We recently documented the natural, stepwise evolution over 45 million years of the peptide macrocycle SunFlower Trypsin Inhibitor 1 (SFTI-1) within a preproalbumin host . Here we show how readily proteins can be forced to host interstitial peptides and propose that this might be a more universal type of protein evolution. We made constructs that showed how SFTI-1 could emerge from alternative locations within its preproalbumin host, but did so to the detriment of the albumin. Using constructs for chimeric proteins, SFTI-1 could also emerge with precision from seed proteins completely unrelated to its host by recruiting the appropriate proteolytic machinery. We also found SFTI-1 production was not dependent upon its adjacent albumin, but was greatly reduced without it. Together, these findings show that SFTI-1 is a hijacker rather than a passive passenger within its proalbumin host. We detail a potential second example of hijacking with 4Cys hairpin peptides we find to be similarly buried within precursors for seed vicilin. This second potential example suggests interstitial peptides evolving within protein hosts represent an effective shortcut to evolving new proteins. Hijacking a host protein bypasses many impediments that de novo evolved genes face before encoding a stable, new, functional protein. We have now discovered a spectacular array of peptide topologies that emerge from seed protein hosts and these include (i) tiny, homodetic cyclopeptides called orbitides, (ii) a uniquely large orbitide, (iii) bicyclic, 2Cys peptides, (iv) 2Cys-stapled hairpins, (v) 4Cys-stapled hairpins and (vi) a unique, 4Cys, tricyclic peptide ladder. What else is hiding in protein hosts and how do we find them?