PHP Contact Form (with Recaptcha)

I require somebody to create the PHP function to make the following html code work properly and with a recaptcha where shown.... <form class="customform" action=""> <div class="line"> <div class="margin"> <div class="s-12 l-4"><input name="Name" placeholder="Your Name..." title="Your Name" type="text" /></div> <div class="s-12 l-4"><input name="Tel No" placeholder="Your Tel No..." title="Your Telephone Number" type="text" /></div> <div class="s-12 l-4"><input name="Email" placeholder="Your Email..." title="Your Email" type="text" /></div> </div> </div> <div class="s-12"><textarea placeholder="Your message..." name="Message" rows="5"></textarea></div> <div class="line"> <div class="margin"> <div class="s-12 l-6">Recaptcha goes here...</div> <div class="s-12 l-6"><button type="submit">Submit</button></div> </div> </div> </div> </form> Script must be secure and as lightweight as possible please.