This makes the @Html.EditorFor refer to the Title field of the object, kinda in a random way but it works!
@using (Html.BeginForm ("SearchIndex", "Movies", FormMethod.Get))
{
@Html.EditorFor( x => x.ElementAt(0).Title)
<button type="submit">Search</button>
}
Still couldn't pass input parameter to the URL in the GET.
EDIT:
FINAL SOLUTION:
@Html.TextBox("SearchString")
<button type="submit">Filter</button>
and on the controller side, switch the input parameter. Basically it will automatically recognize the passed parameter.
public ActionResult SearchIndex(string searchString)
{
...
}