“Smallville” (8 p.m., CW): Clark finally meets his long-dead biological mom (Helen

“Smallville” (8 p.m., CW): Clark finally meets his long-dead biological mom (Helen Slater).

“CSI: Crime Scene Investigation” (9 p.m., CBS): Say farewell to Sara Sidle. Tonight’s episode of “CSI: Crime Scene Investigation” will be her last as actress Jorja Fox checks out of the hit drama.

“Law & Order: Criminal Intent” (10 p.m., USA Network): A lady is murdered, and the suspects are the folks in her literary circle. Guest stars include Fisher Stevens.