The Sonic Screwdriver

The Doctor's Sonic Screwdriver is an invaluable multi-purpose gadget which was first used by his second incarnation to unscrew an inspection box on a gas pipe. Since then it appeared many times, it has many functions varying from a radiation detector to a laser beam. Romana constructed a more refined version which the Doctor unsuccessfully attempted to use as his own. The screwdriver was eventually destroyed by the Terileptil while the fifth Doctor struggled to remove an pair of handcuffs. He commented sadly that it was as if he had lost an old friend.