"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel, standing) and Finch (Michael Emerson, seated) since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Giovanni Rufino/CBS ©2012 CBS Broadcasting Inc. All Rights Reserved

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Giovanni Rufino/CBS ©2012 CBS Broadcasting Inc. All Rights Reserved

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Giovanni Rufino/CBS ©2012 CBS Broadcasting Inc. All Rights Reserved

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Giovanni Rufino/CBS ©2012 CBS Broadcasting Inc. All Rights Reserved

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel, right) and Finch (Michael Emerson, left) since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Giovanni Rufino/CBS ©2012 CBS Broadcasting Inc. All Rights Reserved

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Eric Liebowitz/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Eric Liebowitz/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Eric Liebowitz/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.

"Identity Crisis" -- The Machine's latest number presents a unique challenge for Reese (Jim Caviezel, second from left) and Finch since the person has virtually no digital footprint - and appears to be leading a double life, on PERSON OF INTEREST, Thursday, March 29 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Also pictured: Rhys Coiro (far left), Johnny Hopkins (second from the right), Rafael Sardina (far right). Photo: Eric Liebowitz/Warner Bros. ©2012 Warner Bros. Television. All Rights Reserved.