Abstract: A bottle opener for cutting open thermoplastic bottle caps is disclosed. The bottle opener includes a first arm having a proximal end and a distal end, the first arm including at least one transverse aperture. A second arm includes a proximal end and a distal end, the second arm mounting a cutting blade. The first and second arms are joined together at their respective proximal ends and are normally urged apart into an inoperative mode and when urged together into a cutting mode, the cutting blade is moved into a cutting position that traverses the aperture and cuts the top off of a bottle resting therein.