diff --git a/cmd/plan_test.go b/cmd/plan_test.go
index 300a87e..dd010a3 100644
--- a/cmd/plan_test.go
+++ b/cmd/plan_test.go
@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"errors"
 	"testing"
 )
 
@@ -20,6 +21,11 @@ func TestPlan(t *testing.T) {
 			erroutput: "Cloning plan https://github.com/lunarway/shuttle-example-go-plan.git\n",
 			err:       nil,
 		},
+		{
+			name:    "git plan invalid checkout",
+			input:   args("-p", "testdata/project-git", "--plan", "something-invalid", "plan"),
+			initErr: errors.New("Plan argument wasn't valid for a git plan (#<branch / tag name>): something-invalid"),
+		},
 		{
 			name:      "no plan with template",
 			input:     args("-p", "testdata/project", "plan", "--template", "{{.PlanRaw}}"),
diff --git a/pkg/git/git.go b/pkg/git/git.go
index 7c52b0f..6b13982 100644
--- a/pkg/git/git.go
+++ b/pkg/git/git.go
@@ -83,9 +83,13 @@ func GetGitPlan(
 ) (string, error) {
 	parsedGitPlan := ParsePlan(plan)
 
-	if strings.HasPrefix(planArgument, "#") {
-		parsedGitPlan.Head = planArgument[1:]
-		uii.EmphasizeInfoln("Overload git plan branch/tag/sha with %v", parsedGitPlan.Head)
+	if planArgument != "" {
+		if strings.HasPrefix(planArgument, "#") {
+			parsedGitPlan.Head = planArgument[1:]
+			uii.EmphasizeInfoln("Overload git plan branch/tag/sha with %v", parsedGitPlan.Head)
+		} else {
+			return "", fmt.Errorf("Plan argument wasn't valid for a git plan (#<branch / tag name>): %s", planArgument)
+		}
 	}
 
 	planPath := path.Join(localShuttleDirectoryPath, "plan")