diff --git a/.github/workflows/scandir.yml b/.github/workflows/scandir.yml
index c971c91..bc337b1 100644
--- a/.github/workflows/scandir.yml
+++ b/.github/workflows/scandir.yml
@@ -61,3 +61,19 @@ jobs:
           echo "::error:: Expected file $notexpect found in ${{ steps.two.outputs.files }}"
           exit 1
         fi
+
+    - name: Run ShellCheck
+      uses: ./
+      id: three
+      with:
+        scandir: './testfiles/scandir'
+        all_scripts: true
+
+    - name: Verify check
+      run: |
+        expect="testfiles/scandir/unknown-shebang"
+
+        if [[ ! "${{ steps.three.outputs.files }}" =~ $expect ]];then
+          echo "::error:: Expected file $expect not found in ${{ steps.three.outputs.files }}"
+          exit 1
+        fi
diff --git a/action.yaml b/action.yaml
index 130781e..b6417a0 100644
--- a/action.yaml
+++ b/action.yaml
@@ -6,6 +6,10 @@ inputs:
     description: "A space separated list of additional filename to check"
     required: false
     default: ""
+  all_scripts:
+    description: "Set to true to check all executable scripts. The default is to check only ones with known shebangs"
+    required: false
+    default: ""
   ignore:
     description: "Paths to ignore when running ShellCheck"
     required: false
@@ -147,6 +151,7 @@ runs:
       shell: bash
       id: check
       env:
+        INPUT_ALL_SCRIPTS: ${{ inputs.all_scripts }}
         INPUT_SCANDIR: ${{ inputs.scandir }}
         INPUT_CHECK_TOGETHER: ${{ inputs.check_together }}
         INPUT_EXCLUDE_ARGS: ${{ steps.exclude.outputs.excludes }}
@@ -155,7 +160,8 @@ runs:
       run: |
         statuscode=0
         declare -a filepaths
-        shebangregex="^#! */[^ ]*/(env *)?[abk]*sh"
+        shebangregex="^#!"
+        [ "$INPUT_ALL_SCRIPTS" = "true" ] || shebangregex="^#! */[^ ]*/(env *)?[abk]*sh"
 
         set -f # temporarily disable globbing so that globs in inputs aren't expanded
 
diff --git a/testfiles/scandir/unknown-shebang b/testfiles/scandir/unknown-shebang
new file mode 100755
index 0000000..05ec3e9
--- /dev/null
+++ b/testfiles/scandir/unknown-shebang
@@ -0,0 +1,3 @@
+#!/usr/bin/with-contenv bashio
+
+echo "hi"
\ No newline at end of file