Provided are bispecific T Cell Engagers. More specifically, the invention is directed to bispecific molecules that bind to DLL3, MUC17 or CLD18 and activate CD (cluster of differentiation) molecules (e.g. CD3, CD28 and CD137). Also provided are methods of treating an ailment such as cancer using an antibody (or fragment) against DLL3, MUC17 or CLD18 paired with an antibody (or fragment) of an agonist antibody that activates CD3, CD28 and/or CD137.