Splice from multi-dimensional array?

Hi all

I have multi-dimensional array - 3 arrays inside another array.

I want to splice from one of the arrays and replace the removed item.

How can I splice from a multi-dimensional array?

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>

	<title>Splice from multi-dimensional array</title>
	
</head>

<body>

  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
  <script type="text/javascript">
    
    var colors_arr = new Array();
    var numbers_arr = new Array();
    var names_arr = new Array();
    var all_arr = new Array();
    //
    colors_arr.push('red','green','blue','black','yellow');
    numbers_arr.push('one','two','three','four','five');
    names_arr.push('Chris','John','Jack','Sarah','Jane');
    //
    all_arr.push(colors_arr);
    all_arr.push(numbers_arr);
    all_arr.push(names_arr);
    //
    alert(all_arr[2]);
    
    var arr = 2;
    var item = 2;
    var replace = 'Jill';
    
    all_arr.splice([arr][item],1, replace);
    
    alert(all_arr[2]);
    
    
  </script>
</body>
</html>