The Trickster poisons people at the Mayor's press conference that Iris is attending in episode 1x17 "Tricksters".
Barry and Cisco go to meet with Lila to get the alien power source to power their Speed Force Bazooka but she turns them down in episode 3x22 "Infantino Street".
Cyborg Superman breaks into the lobby of L Corp to steal the isotope needed to use the Medusa virus but is thwarted by Kara in episode 2x08 "Medusa".
Source: What's Filming
Lyra takes Winn to the art gallery and convinces him that they should break in to have some hot museum sex in episode 2x16 "Star-Crossed".