diff --git a/lib/monitor/run.js b/lib/monitor/run.js
index e316c2b1..4c74d338 100644
--- a/lib/monitor/run.js
+++ b/lib/monitor/run.js
@@ -91,7 +91,7 @@ function run(options) {
   const shouldFork =
     !config.options.spawn &&
     !inBinPath &&
-    firstArg.indexOf('-') === -1 && // don't fork if there's a node exec arg
+    !(firstArg.indexOf('-') === 0) && // don't fork if there's a node exec arg
     firstArg !== 'inspect' && // don't fork it's `inspect` debugger
     executable === 'node' && // only fork if node
     utils.version.major > 4 // only fork if node version > 4