1. **State the problem:** Simplify the expression $-1 - 3 - (-9) + (-5)$. 2. **Recall the rules:** Subtracting a negative number is the same as adding its positive counterpart, so $- (-9) = +9$. 3. **Rewrite the expression:** $$-1 - 3 + 9 - 5$$ 4. **Perform the operations from left to right:** $$(-1 - 3) + 9 - 5 = -4 + 9 - 5$$ 5. **Continue simplifying:** $$(-4 + 9) - 5 = 5 - 5$$ 6. **Final step:** $$5 - 5 = 0$$ **Final answer:** $0$