She was featured on the cult hit ``Alias,’’ has had memorable roles in ``Malcolm in the Middle’’ and ``King of Queens’’ and now stars in ``Summerland’’ (tomorrow at 9 p.m. on WLVI, Ch. 56), the one new show of the summer considered a hit. But Merrin Dungey doesn’t consider herself lucky.

``My dad gave me advice,’’ Dungey said during a recent telephone interview. ``He said, `Luck exists at the corner of opportunity and persistence.’ There’s no such thing as straight-up luck. I worked my ass off.’’

Dungey joined the WB series after the initial pilot already had been filmed, but producers were looking to recast the part of Ava’s (Lori Loughlin) best friend Susannah.

``Allison got stabbed yet again on `Alias,’ ’’ she said. ``This script came along and I thought, `I’ll go in, it’s Aaron Spelling.’ Executive producers Remi Aubuchon and Stephen Tolkin were making a lot of changes to the script. They wanted to bring a lot of who I am to the character. They really wanted to make it funnier. A balance of humor and sensitivity, this was really what I can bring to the character.’’

Dungey’s Susannah is helping to raise Ava’s three nieces and nephews whose parents died in the first episode. ``There was lots of groundwork they had to lay in the pilot,’’ Dungey said. ``Now the roots are taking hold. The show surprises me every day. It’s much deeper than I thought it would get. There’s actual conflict between Ava and I and what’s going on with the adults in the house. Where their lives are headed is taking shape. Susannah is really questioning what her role is.’’

Loughlin also serves as the producer of the series. ``It’s great because she is on our side about so many different things and has that perspective,’’ Dungey said. ``Something we have a problem with - she’s there and she sees it. It’s really fantastic. It’s her passion and enthusiasm for really making the product amazing. Lots of our improv came out of how well we get along. One day, Lori turned to me and said, `I think you and I have the best chemistry on the show.’ ’’

Dungey has yet to meet her series’ most famous executive producer face-to-face. ``I haven’t had a chance to meet Aaron Spelling,’’ she said. ``I’m a huge fan. When I was little, I used to audiotape `Charlie’s Angels,’ and then we’d play `Charlie’s Angels’ on our bikes.’’

Going from hand-to-hand combat with ``Alias’’ star Jennifer Garner to working with three young actors on ``Summerland’’ has been an adjustment.

``We have to watch our language. We have a dollar swear jar,’’ she said, laughing. She recently took co-star Kay Panabaker (Nikki) shopping for a prom dress.

Dungey’s parents wanted her to get a teaching certificate so she would have something to fall back on. But Dungey, who graduated with a bachelor of arts from the UCLA School of Theater, told her parents, `` `I need to fall forward.’ ’’

``I never got an office job,’’ she said. ``I was a personal assistant to Faye Dunaway and the president of Warner Bros. I could do that and leave and go to auditions.’’

There are still two shows Dungey would love to be on - ``24’’ and ``The O.C.’’

``I went up to the executive producer of `The O.C.’ and said, `A) You need to put black people on the show, and B) one of them needs to be me.’ No one they interact with is of color. The principal is Asian, and she’s been on twice. It’s 2004. You’ve got to mix it up.’’

Although her ``Alias’’ character Francie and her evil doppelganger Allison have died multiple times on ``Alias,’’ Dungey hasn’t ruled out a return appearance on the series.

``You never ever know, nothing is certain with executive producer J.J. Abrams,’’ she said. ``Things are shifting again. Everyone talks about if the show is going to jump the shark, but this shark just keeps swimming. J.J. changes the rules of the game every six months. If they ever make `Alias’ the movie, I better be coming back.’’