ElementStacks

HTML

<script src="http://highcharts.com/js/testing.js"></script>
<div id="container" style="height: 400px; width: 500px"></div>
<button>Remove series 1 from the legend</button>

JavaScript

window.chart = new Highcharts.Chart({
    chart: {
        renderTo: 'container'
    },    
    series: [{
        data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0]
    },{ 
        data: [135.6, 148.5, 216.4, 194.1, 95.6, 54.4]
    }]
}, function(chart){
    
    $('button').click(function(){
        // change series options
        var series = chart.series[0],
            visible = series.options.showInLegend = !series.options.showInLegend,
            toggle = visible ? 'show' : 'hide';
        
        series.legendItem[toggle]();
        series.legendLine[toggle]();
        series.legendSymbol[toggle]();
        
        // render legend
        chart.legend.renderLegend();
    })
        
});