Team Arrow and A.R.G.U.S. must defend the data center from Hive attack while Felicity and her father shut down the missiles in episode 4x21 "Monument Point".
Felicity and her father escape Palmer Tech with Lance's help in episode 4x21 "Monument Point".
Thea tries to convince Lonnie Machin not to blow up the air filtration system in the dome in episode 4x21 "Monument Point".
Oliver tracks Ragman to the gun exchange between Church and Janet Carroll in episode 5x02 "The Recruits".
Felicity and Curtis track Black Siren's target to the stadium and Oliver is unsuccessful at getting the concert shut down in episode 6x07 "Thanksgiving".
Livewire is being tortured to extract her powers by a mad scientist at an abandoned power company. Guardian and Mon-El arrive to rescue her but get in over their heads until Supergirl arrives in episode 2x10 "We Can Be Heroes".
Maggie and the cops show up to find a criminal tired up for them by Guardian in episode 2x10 "We Can Be Heroes".