diff --git a/MagickCore/fx.c b/MagickCore/fx.c
index 8492856075..dc96e9bdd2 100644
--- a/MagickCore/fx.c
+++ b/MagickCore/fx.c
@@ -2249,12 +2249,22 @@ static MagickBooleanType GetOperand (
       }
       return MagickTrue;
     } else if (OprIsUnaryPrefix (op)) {
+      MagickBooleanType operand_ok;
       if (!PushOperatorStack (pfx, (int) op)) return MagickFalse;
       pfx->pex++;
       SkipSpaces (pfx);
       if (!*pfx->pex) return MagickFalse;
-
-      if (!GetOperand (pfx, UserSymbol, NewUserSymbol, UserSymNdx, needPopAll)) {
+      if (pfx->teDepth >= MagickMaxRecursionDepth) {
+        (void) ThrowMagickException (
+          pfx->exception, GetMagickModule(), OptionError,
+          "Expression too deeply nested", "(depth %i exceeds limit %i)",
+          pfx->teDepth, MagickMaxRecursionDepth);
+        return MagickFalse;
+      }
+      pfx->teDepth++;
+      operand_ok=GetOperand (pfx, UserSymbol, NewUserSymbol, UserSymNdx, needPopAll);
+      pfx->teDepth--;
+      if (!operand_ok) {
         (void) ThrowMagickException (
           pfx->exception, GetMagickModule(), OptionError,
           "After unary, bad operand at", "'%s'",