Main Door Locking Mechanism

The TARDIS lock and TARDIS key

A TARDIS's Main Doors are protected by a double-curtain trimonic barrier, which is controlled by the Primary Threshold Systems. The lock is electronic and uses a meson projection system to read the Trimonic Cypher-Indent Key to ensure that it has the correct crystalline molecular structure/code. If the code is correct, the Threshold Systems unlock the outer doors.

Another security measure is the "21 position lock." When it is enabled, the locking mechanism extends out of the shell and presents the user with 21 different key holes. If the wrong key hole is used, the whole mechanism fuses. Using the Control Console, the Doors can be Double-Locked from the inside. This prevents the Key from working in the lock. If the lock is unresponsive to the Key then the operator can use his "stone with great power" (usually set into a piece of jewelry such as a ring) to refract sunlight into the lock and return it to operational status.

Normally a TARDIS's safety functions will not allow dematerialization while the Key is in the locking mechanism. But if the TARDIS is in Pause-Control, then inserting the key for more then 20 seconds will cancel Pause-Control and initiate dematerialization.

Type 53 and later TARDISES have Exterior Sensor Plates that the operator can unlock by holding the Key against the plate. Some of the newer TARDISes built around the time of "Genesis of the Daleks" (Probably the Type 7-0-6) have pure mind locks rather than key or touch activated ones. Type 89 TARDISes (aka Type 102s) have locks with voice prints.

If someone tries to cut out the Lock, then a defense mechanism will destroy any mechanical saw blades in a flash of blue light. However, if a TARDIS is suffering the right type of malfunction and someone has some simple electronic lock picking tools, the entire exterior locking mechanism can be removed, making entry impossible even with the Cypher-Indent Key. TARDIS keys are largely the same and it is fairly easy to use a key from one TARDIS to pick the lock of another TARDIS. With great difficulty, a TARDIS lock can be picked with a Sonic Screwdriver using the Devlin principle of randomized mathematical probability to generate the possible key combinations. A being with incredibly strong psionic powers can force a TARDIS's Main Doors open from the outside. Such an attack would probably cause the Relative Continuum Stabilizer to fail.

Color Key

The following color code is used:

Copyright Will B Swift


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