The pair will play rivals on an episode of McDermott's fall Fox comedy 'L.A. to Vegas.'

After years of enduring gags about their similar names, and the vague resemblance they share, Dylan McDermott and Dermot Mulroney are finally going head-to-head.

Mulroney is set to guest-star on an episode of Fox's upcoming comedy (and McDermott vehicle) L.A. to Vegas. Not content to just have the two actors share screen time for the first time ever, they'll also be playing rival airline pilots.

Mulroney will play Capt. Steve, a charismatic pilot with better international routes and an attitude that grinds on McDermott's Capt. Dave. Strangely, this is the first time the two actors have performed together. In 2012, Mulroney appeared as himself (and McDermott, sort of) in a Saturday Night Live skit about a game show where contestants unsuccessfully tried to tell them apart.

L.A. to Vegas, set to debut midseason, is a workplace comedy from 20th Century Fox TV that follows an airline crew and their rotating passengers as they fly roundtrip from Burbank to Las Vegas. It also stars Ed Weeks, Kim Matula, Nathan Lee Graham, Olivia Macklin and Peter Stormare. Production on the freshman series kicked off earlier in the week.

Mulroney is repped by WME.