Everyone is shocked when Douglas introduces a fourth bionic sibling named Daniel who’s been living a normal life with an adopted family. Daniel later comes to the academy to meet his father, uncle, and cousins. After Daniel's bionics are accidentally activated by the Lab Rats, Donald and Douglas find out what happened they have to come clean to Daniel about his power-replicating abilities. Daniel also finds out that his cousins are actually his biologic siblings. Filled with anger, Daniel goes out for air on the beach, where Leo and him have a conversation about Douglas. Not too long after, Daniel, using Leo's abilities, accidentally causes a leak in the hydro-loop's fuel tank. After Adam and Daniel combined their powers to stop it, Douglas apologizes to Daniel for lying and Daniel decides to give Douglas a second chance.
Lab Rats — Season 4 Episodes (26)
EP 1
E1
EP 2
E2
EP 3
E3
EP 4
E4
EP 5
E5
EP 6
E6
EP 7
E7
EP 8
E8
EP 9
E9
EP 10
E10
EP 11
E11
EP 12
E12
EP 13
E13
EP 14
E14
EP 15
E15
EP 16
E16
EP 17
E17
EP 18
E18
EP 19
E19
EP 20
E20
EP 21
E21
EP 22
E22
EP 23
E23
EP 24
E24
EP 25
E25
EP 26
E26