diff --git a/dust-lang/src/instruction.rs b/dust-lang/src/instruction.rs
index 5d2e3d6..371f4dc 100644
--- a/dust-lang/src/instruction.rs
+++ b/dust-lang/src/instruction.rs
@@ -573,15 +573,12 @@ impl Instruction {
             Operation::Call => {
                 let function_index = self.a();
                 let argument_count = self.b();
+                let first_argument = function_index + 1;
                 let last_argument = function_index + argument_count;
 
                 let mut output = format!("R{function_index}(");
 
-                for register in function_index..last_argument {
-                    if register != last_argument - 1 {
-                        output.push_str(", ");
-                    }
-
+                for register in first_argument..=last_argument {
                     output.push_str(&format!("R{}", register));
                 }
 
diff --git a/dust-lang/src/parser.rs b/dust-lang/src/parser.rs
index bbbf828..8c8d29e 100644
--- a/dust-lang/src/parser.rs
+++ b/dust-lang/src/parser.rs
@@ -1159,9 +1159,11 @@ impl<'src> Parser<'src> {
 
         self.advance()?;
 
-        let function_register = self.current_register - 1;
+        let function_register = self.current_register;
         let mut argument_count = 0;
 
+        self.increment_register()?;
+
         while !self.allow(Token::RightParenthesis)? {
             if argument_count > 0 {
                 self.expect(Token::Comma)?;
diff --git a/dust-lang/src/vm.rs b/dust-lang/src/vm.rs
index be14c53..df528f6 100644
--- a/dust-lang/src/vm.rs
+++ b/dust-lang/src/vm.rs
@@ -382,9 +382,9 @@ impl Vm {
                     };
                     let mut function_vm = Vm::new(function.take_chunk());
                     let first_argument_index = function_index + 1;
-                    let last_argument_index = first_argument_index + argument_count;
+                    let last_argument_index = first_argument_index + argument_count - 1;
 
-                    for argument_index in first_argument_index..last_argument_index {
+                    for argument_index in first_argument_index..=last_argument_index {
                         let argument = self.empty(argument_index, position)?;
 
                         function_vm.stack.push(Register::Value(argument));