Rob Lowe and Fred Savage take comedy to new legal highs as odd-couple brothers in The Grinder

Rob Lowe, left, and Fred Savage play brothers in new television comedy The Grinder. Ray Mickshaw / FOX via AP

The most shocking thing about The Grinder is how many years it took for TV bosses to realise that there could be such wonderful comic chemistry between Rob Lowe and Fred Savage, two reliable laugh-getters who have each proven themselves in hit sitcoms.

This new Fox sitcom about odd-couple sibling rivals at a family law firm in small-town Idaho, which debuts tonight on OSN First Comedy, quickly established itself as a critics’ darling when it debuted in the United States in September. It has a 93-per-cent approval rating on the Rotten Tomatoes review website, and Lowe was nominated for a ­Golden Globe.

"Rob Lowe and I play brothers, which I feel like has been a long time coming," says Savage, 39, who is still fondly remembered as the child star of The Wonder Years, in which he starred as Kevin Arnold, a youngster growing in an American suburb in the 1960s and 1970s.

“I feel like showbiz has just caught up to what America’s been thinking.”

Former 1980s Brat Pack member Lowe, 51, plays Dean Sanderson, a famous TV actor whose popular, long-running TV legal drama, called The Grinder, has just ended. He opts to leave the glare of Hollywood behind and return to his hometown of Boise, Idaho, where his father Dean Sr, played by 24 and Knots Landing star William Devane, and brother Stewart (Savage) run Sanderson & Yao, the family law firm.

"He has been starring as a ­lawyer in The Grinder for seven seasons, and it's the biggest show on television," Lowe says of his character, "and now it's over. He gets it in his head that what he wants is normalcy. And a life of value."

Brotherly sparks fly when Dean, who has no formal legal training, decides he wants to practise law, straightaway, and after seven years playing a lawyer on TV, he reckons he doesn’t need to bother with the hassle of going to law school. After all, he’s famous, and his acting smarts as a TV lawyer will carry the day in the real world. Right?

Stewart’s dream of taking over the family firm from his father are soon in tatters, as Dean’s courtroom theatrics easily outshine Stewart’s mumbling, awkward ways. He is more used to behind-the-scenes desk work, shuffling papers and crafting contracts, and is completely lacking in courtroom charisma. It hardly helps, either, that Dean is dad’s favourite.

There’s a big thumping heart at the centre of this sitcom – the fact that the brothers each want what the other has achieved in life, while deep down they truly do care for, and support, each other.

“People appreciate [Dean] and value him and think he’s great,” says Savage, “and he has this ‘sizzle’ and a way with people that [Stewart] could only hope to have. And conversely, Dean sees in Stewart a guy who has a family and has a home and has roots and has people who love him.”

Dean is hungry for "an authentic life," says Lowe, whose movie career included early hits such as St. Elmo's Fire (1985) and About Last Night (1986). More recently, he's made his mark as a top television actor, most notably in early seasons of Aaron Sorkin's political drama The West Wing, followed by the family drama Brothers & Sisters and the comedy Parks and Recreation.

Rounding out the cast are: Mary Elizabeth Ellis (It's Always Sunny in Philadelphia, Perfect Couples) as Stewart's devoted wife Debbie, and Natalie Morales (The Middleman, Going The Distance) as Claire Lacoste, a newly ­arrived law-firm associate who shrugs off Dean's romantic ­advances.

The toughest part of casting for The Grinder was convincing Fred Savage to step back in front of the camera, away from a flourishing career as a director of ­episodes of prime-time network hits including Modern Family and 2 Broke Girls.

“Watching Fred do this was, like, this incredible kick and thrill,” says the executive producer and director Jake Kasdan. “He is so funny and loose and quick and loveable, and this is, like, a perfect, incredible thing we tripped into here … We had to pull him kicking and screaming back into acting, and we lucked out.”

As for what attracted Lowe to the role, he says: "I learnt a tremendous amount from The West Wing. I learnt a lot from Parks and Recreation and Brothers & Sisters. You learn the good things, you learn the bad things, the cautionary tales, all of it.

"I feel like everything has led to this, both in terms of what I know today and my ability to play a guy like The Grinder.

“I don’t know how many episodes of television I’ve done – but it’s a lot – and so it’s a perfect time for me to play a guy who’s done a lot of episodes of ­television.”

•The Grinder begins at 8pm tonight on OSN First Comedy HD