"The Man Who Toppled the Titans"
*After a two-year hiatus, during which Mr. Jupiter has closed down his training program and Mal has been left in charge of the Teen Titans base and equipment while the team formally broke up so that its super-hero members could pursue their individual careers, the members receive an emergency signal which rallies Robin, Kid flash, Wonder Girl, Speedy, and Mal to their former headquarters. This turns out to be a trap set by Dr. Light, who intends to use the Titans as bait to trap the Justice League. He defeats the team in battle and captures Robin and Wonder Girl, then stops Kid flash and Speedy before they can warn their adult counterparts of his plans. Mal appropriates an exo-skeleton (used against Robin in Batman #192) and the Guardian's costume (left in the keeping of Speedy, who is revealed as the Guardian's nephew in Superman Family #191-194) from the Titans' storeroom to become the new Guardian, in which identity he is able to free his captive fellow members. Together, the revived Titans defeat Dr. Light and stop his plan to take over the JLA satellite. *Source: Official Teen Titans Index #2 - Published by ICG
Speedy gets a new costume and Malcolm "Mal" Duncan becomes the Guardian.