Disclosed herein are 1,2,3,4-tetrahydroisoquinolines and 4, 5, 6, 7-tetrahydrothieno [2, 3-cjpyridines, useful as antagonists of the muscarinic acetylcholine receptor M4 (mA·Ch·RM4). Also disclosed herein are methods of making the compounds, pharmaceutical compositions comprising the compounds, and methods of treating disorders using the compounds and compositions.