CHICAGO (thefutoncritic.com) -- Tom Selleck has signed a deal to appear in the final four episodes of NBC's "Third Watch" this season while Andie MacDowell and Teri Polo are set for guest spots on ABC's struggling drama "The Practice."

Selleck, best known for his work on "Magnum, P.I," will guest "as a hard-living journalist with a secret who becomes romantically involved with paramedic Kim (Kim Raver) -- and works as a confidential police informant" on the Peacock drama, according to NBC's latest press release. The news comes after the actor's recent commitment to a new comedy pilot, "Touch 'Em All McCall," at the network. Selleck's episodes will begin airing some time in April.

Meanwhile, Teri Polo ("Meet the Parents") has signed on to replace Bridget Fonda for a three-episode stint on David E. Kelly's "The Practice." Fonda was injured in a car accident recently and had to bow out of the role. Polo will play an old flame of Dylan McDermott's character who puts a strain on his marriage. No specific air dates have been set. Polo recently signed on as the female lead in ABC's untitled Henchy/Pennette comedy pilot.

As for MacDowell, the actress will guest in an upcoming episode in a storyline involving Jimmy Berluti (Michael Badalucco). MacDowell filmed a pilot last season ("Jo") for CBS that was not picked up.