 In the season eight episode " Bride " , Oliver Queen ( Justin Hartley ) , believing he is tracking Lex Luthor who has been missing since the season seven finale , discovers Lana instead . Oliver convinces her to return to Smallville so that she can attend Chloe 's wedding . In the season eight episode " Power " , it is revealed that Lana really returned so that she could steal Lex 's " Prometheus " technology , which harnesses alien DNA to give the wearer of a " super @-@ suit " superhuman abilities , for herself . By the end of the episode , the procedure is complete , and Lana becomes just as strong and invulnerable as Clark . In the episode " Requiem " , Lana discovers that her suit absorbs kryptonite , but also emits the radiation making her a potential danger to Clark . When Winslow Schott puts a kryptonite bomb on the roof of the Daily Planet , Lana is forced to absorb all of the kryptonite to deactivate the bomb . As a result , she leaves Smallville to go on her own quest as Clark can no longer get near her without the kryptonite radiation hurting him . 
