According to The Hollywood Reporter, O'Donnell and LL Cool J are in talks to topline the "NCIS" episode that will air this spring and operate as a backdoor pilot for the possible spinoff.
"NCIS," of course, began its life in similar fashion as a backdoor pilot spinning off from "JAG."
The trade paper says O'Donnell would play Callen, an agent whose average exterior makes it easy for him to take on a variety of different identities and perform undercover work.
LL Cool J would play former Navy Seal Sam Hannah.
The rapper and thespian has been in CBS' crosshairs for some time. He starred in the network's 2007 pilot "The Man" and even when that drama wasn't sent to series, CBS attempted to redevelop the project just to stay in business with LL Cool J, whose other acting credits include "Deep Blue Sea" and "S.W.A.T."
"Scent of a Woman" and "Batman and Robin" star O'Donnell hasn't hesitated to take small screen work in recent years. In addition to a multi-episode arc on ABC's "Grey's Anatomy," he starred on FOX's short-lived "Head Cases" and in TNT's miniseries "The Company."